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No presente estudo, procedeu-se à caracterização tecnológica dos caules de quatro variedades de mandioca (Manihot esculenta Crantz) - IAC 12.829, Branca de Santa Catarina, Roxinha ou Mico e Fibra - como fonte de fibras celulósicas para a produção de celulose e papel. Os resultados mostraram que os rendimentos em fibras celulósicas dos caules de mandioca variaram de 239,7 a 317,6 g/kg. As variedades Fibra e Branca de Santa Catarina, respectivamente, foram as que apresentaram o menor (18,2 g/kg) e o maior (35,0 g/kg) teor de fração medular. As frações lenhosas do caule forneceram fibras mais curtas (0,77 a 0,96 mm) que as liberianas (1,71 a 2,61 mm). As relações entre as dimensões das fibras indicaram valores adequados à produção de celulose e papel com boas características físico-mecânicas. The technological characterization of stems of four manioc varieties (IAC 12.829, Branca de Santa Catarina, Roxinha or Mico and Fibra) were determined, in order to evaluate the cellulosic fibers as raw material for pulp and paper production. The results showed that the cellulosic fiber yields of the cassava stem varied from 239.7 to 317.6 g/kg. The 'Fibra' and 'Branca de Santa Catarina' varieties presented, respectively, the smallest (18.2 g/kg) and the highest (35.0 g/kg) medullary contents. The cassava stem woody portion supplied cellulosic fibers (0.77 to 0.96 mm) shorter than the fibers of the best fraction (1.71 to 2.61 mm). The relation between fiber dimensions pointed out adequate values to produce pulp and paper with good physical and mechanical properties.

São apresentados e discutidos os resultados das medições de comprimento e largura das fibras de 27 espécies alienígenas de bambus, compreendendo 12 gêneros, das quais apenas 4 foram anteriormente estudados pelos autores. O material usado nos exames biométricos das fibras de 19 das novas espécies estudadas, foi coletado do "bambusetum" localizado na Estação Experimental de Tatuí, sendo que o dos 4 restantes do base do côlmo de mudos importadas do estrangeiro, mas que não vingaram. Os resultados dos medições mostram que as dimensões das fibras, em comprimento e largura, variaram grandemente segundo as espécies de bambu. O comprimento médio de fibra variou de 1,33 a 2,74 mm, enquanto que a largura variou de 8,39 a 20,90 microns. A relação entre o comprimento e a largura das fibras situou-se entre 63:1 a 264:1. Os resultados encontrados nas medições de comprimento das fibras confirmam, de modo geral, o valor dos bambus como matéria-prima para produção de celulose de fibras longas. This article gives fiber dimensions and derived values obtained for 23 bamboo species, besides similar data for 4 species previously reported by the authors. The average fiber dimensions found for the 27 bamboo species ranged as follows (in milimeters): length, from 1.325 for Bambusa beecheyana to 2.744 for Gigantcchloa apus; width, from 0.00839 for Pleioblastus simoni to 0.02090 for Bambusa beecheyana. The length diameter ratio ranged from 63:1 to 264:1, the shortest ratio being that of Bambusa beecheyana and the highest one of Bambusa vulgaris. The coefficient of variation for fiber length ranged from 26.50% to 42.32% and for fiber width from 17.80% to 60.09%. Considering the ease of bamboo cultivation, the high and rapid production per area, and the quality of the fiber, bamboos areunquestionably the most promising source for cellulose production in the tropical and subtropical regions. As in many other countries where bamboo is being used on a large scale for the pulp and paper industry, it seems likely that in Brazil this plant as a commercial crop will be, in very near future, an important source of long-fibered pulp for blending with short-fibered pulps in papermaking.

ABSTRACT: Description and prediction of water flow through unsaturated soils is necessary to understand their hydraulic properties, including soil water retention curve (SWRC). Many models have been developed for estimation of SWRC and many researchers compared water retention curve derived from these models with the measured values. In this paper, in addition to comparing measured and derived SWRC, a functional evaluation of SWRC for modeling of soil water movement was carried out using van Genuchten, Brooks-Corey, Campbell and Hutson-Cass models in three sites including Loamy sand, Loam and Clay loam soils. Therefore, the functional behavior of SWRC was quantitatively compared by applying mentioned SWRC to numerical code (HydroGeoSphere) to simulate soil profile drainage under steady-state and transient conditions. The agreement between simulated and measured free drainages values was evaluated using statistical criteria including mean absolute error (MAE), modified index of agreement (d’), modified coefficient efficiency (E’), and t-test. The results demonstrated that the van Genuchten model was slightly better than the other models for estimation of SWRC (MAE 0.014 – 0.016,E’ 0.80 – 0.87 and d’ 0.90 – 0.93) while according to t-test, it was found that the measured and estimated SWRC using various models did not differ significantly. Therefore, it is expected that the simulated free drainage using mentioned SWRC models did not differ significantly with observed values. But the results demonstrated that the simulated free drainage using Brooks-Corey model for Loamy sand soil and van Genuchten and Brooks-Corey models for Loam soil differed significantly (p ≤ 0.05) with measured values.

Sisal (Agave sisalana Perrine) accounts for about one half of the world's production of hard fibers. In spite os its economic importance pratically no research work has been carried out on this plant. Very little is known about the agronomic problems of its cultivation, while the physiological and genetic problems are nearly unknown. This is perhaps due to the fact that A. sisalana is a perennial plant with a life cycle of 5-8 years and the carrying out of field research work requires a great deal of time and is very expensive. This paper, the first of a series to be published on the agronomic problems of sisal cultivation, presents the data obtained from field trials on distance of planting and its relation to weight and number of leaves produced. The experiments were carried out at the Ribeirão Preto and Pindorama Experiment Stations of the Instituto Agronômico de Campinas. Sisal bulbils about one year old were planted in the latter part of 1939 in 4 randomized blocks of 9 plots each where different distances between and within the rows were used. Production data were obtained by cutting the leaves at one year intervals begining 2 ½ years from date of planting in the field. Only those leaves that were attached to the plant at an angle greater than 45.° in relation to the main axis of the plant were cut each year. Only in the trial at Ribeirão Preto the leaves were counted and weighted by plants. In the poling plants all leaves than existing were taken off, even the youngest ones adjacent to the pole (flower stalk). Descorticator machine for fiber extraction was not available, so that reliable data on fiber yield could not be obtained. A "probable" fiber yield was obtained by using 3% of leaf w r eight as a basis for calculations. This percentage is recognised as an average fiber content usually obtained from sisal leaves. From the data obtained from the spacing trials described in this paper the following conclusions can be drawn : 1. The life cycle from date of field planting to poling stage of most of the sisal plants in these trials varied from 5 to 8 years. A very small number of plants however had not poled even after 8 years when the present experiments were ended. 2. The life cycle of the sisal plants showed a close relationship to planting distances. At the greater planting distances the plants tended to pole much earlier than at closer planting distances. 3. It was observed that there was a marked seasonal incidente of poling. The flower stalk of almost all plants have appeared during the period of January to March. 4. A marked effect to the distance os planting on plot yields, as measured by total leaf weight, was observed. The greater the density of plants per unit area the greater the leaf production. 5. Under present leaf cutting practice, e. g., to cut yearly only the leaves at an angle greater than 45.° in relation to the main axis of the plant, the shorter distances between the rows are not recommended. The narrow spacing between rows not only restricts the passage of workers, but also hinders adequate cultivation (weeding and sucker growth control). 6. The planting distances of 2 x 2 meters (2500 plants per hectare) was the worst spacing tried. Besides giving a low plant density per unit area it prevents ingress to the planting from any direction. 7. To increase plant density per unit area the closing up of plants within rows is more indicated than closing up the distance between rows. 8. The advantages of the distances of planting between rows of 2.40 or 3.00 meters and 1.20 meters within rows, under present leaf cutting practice, are many. It facilitates weeding, control of suckers growth, and leaf cutting operations.

Neste artigo os autores relatam os resultados obtidos em 10 ensaios, instalados em sete diferentes localidades e abrangendo os principais tipos de solo do Estado de São Paulo. Esses ensaios foram realizados entre 1949-50 e 1953-54 e, excetuando-se um, foram conduzidos por dois ou três anos nos mesmos canteiros, fornecendo, ao todo, 22 resultados anuais. O objetivo em mira foi estudar a melhor época para a aplicação do azôto e do potássio, sendo estes nutrientes, assim como o fósforo, empregados sozinhos ou em diversas combinações. O azôto foi usado na forma de salitre do Chile e, conforme o ensaio, nas doses de 20 ou 30 kg/ha de N; o fósforo como superfosfato, na dose de 60 kg/ha de P2O5; o potássio como cloreto, nas doses de 30 ou 40 kg/ha de K2O. Em média dos ensaios, o efeito do azôto aplicado em cobertura 30-40 dias após a emergência das plantas foi muito superior ao do empregado por ocasião do plantio, nos sulcos destinados às sementes, sendo também maior que o da aplicação em cobertura feita 60-80 dias após a emergência. O fracionamento da dose de azôto em duas porções iguais - estudado em quatro ensaios, compreendendo oito resultados anuais - mostrou-se ainda superior à aplicação da dose total 30-40 dias após a emergência. Quando as duas porções- foram aplicadas em cobertura o efeito do azôto foi bem maior que nas combinações de épocas em que uma das porções foi empregada por ocasião do plantio. Um exame retrospectivo, baseado nos presentes ensaios e nos relatados em artigo anterior, perfazendo 30 resultados anuais, confirmou integralmente as conclusões acima, mostrando que é inútil tentar-se avaliar o efeito dos adubos azotados solúveis empregando-os nos sulcos de plantio, conforme o hábito arraigado em nosso meio, e que a aplicação em cobertura, pouco antes ou logo que aparecerem no algodoal os primeiros botões florais, geralmente dá bons resultados. Nos ensaios em que se pôde determinar a influência das épocas de aplicação sobre o efeito do potássio, as aplicações em cobertura se mostraram inferiores ao emprego nos sulcos de plantio. Neste caso, porém, os resultados só foram satisfatórios quando choveu nos dias imediatos à semeação. Aplicado em cobertura, aparentemente o potássio não penetrou no solo em tempo útil para o algodoeiro; aplicado nos sulcos, êle ficou em posição acessível às raízes, mas, quando correu sêco o período que se seguiu ao plantio, prejudicou o "stand" e a produção. Sendo geralmente pequeno o risco de lixiviação imediata do potássio, sugere-se que êle seja aplicado antes ou por ocasião do plantio, em posição de fácil acesso às raízes, mas não em contato com as sementes. In this paper are reported the results obtained in 10 experiments located at seven different sites comprising the main soil types of the State of São Paulo. Such experiments were carried out from 1949-50 to 1953-54 and, with exception of one, were conducted on the same plots for two or three consecutive years, giving a total of 22 annual results. The rates of application were 60 kilograms of P2O5 per hectare and, according to the experiment, 20 or 30 kilograms of N and 30 or 40 kilograms of K2O per hectare, these nutrients being applied alone or in several combinations. Nitrogen, phosphorus and potassium were used respectively as Chilean nitrate, superphosphate and potassium chloride. Phosphorus was always applied at planting time, whereas nitrogen and potassium were applied at three different times: at planting, 30-40 and 60-80 days after the emergence of the plants. The fertilizers applied at planting time were, as usually, added to the furrows opened for the seed and slightly mixed with the soil just before planting; the applications after the emergence were done as top-dressing. The response.to nitrogen was generally much greater when it was top-dressed 30-40 days after emergence than when the application was done at planting time; the former also gave better results than the delayed top-dressing (60-80 days after emergence). The division of the dose of nitrogen in two equal portions - studied in four experiments, comprising eight annual results - gave still better results than a single application 30-40 days after emergence. When the two portions were top-dressed the response was fairly greater than in the combinations in which one portion was applied at planting time in contact with the seed. A retrospective study based on the present experiments and in others reported in a previous paper, involving 30 annual results, confirmed entirely the above conclusions. In the experiments permitting the comparison of the effect of potassium applied at different times, top-dressing showed to be inferior to the application in the planting furrows. In this case, however, the results were satisfactory only when it rained during the period immediately after planting. Otherwise, germination and stand were impaired. Apparently the top-dressed potassium did not move into the root zone quick enough to benefit the cotton plants when they needed it most; this explains the poor results of that method of application. As the risk of immediate leaching of potassium is generally low, it should be applied before or at planting time in a position easily accessible to the roots, but not in contact with the seed.

Em olericultura o interesse é a produção de produtos comercializáveis. Nesses experimentos, comumente, são avaliadas variáveis tais como a fitomassa das cabeças e ramificações comerciais e não comerciais da planta. No entanto, essas variáveis possuem uma característica particular que está relacionada com a presença ou ausência da estrutura comercial da planta no momento da colheita, o que resulta em valores zeros para essas variáveis, gerando certa variabilidade e afetando a análise de variância dos dados. Assim, este trabalho teve por objetivo definir uma transformação adequada para as variáveis observadas em experimentos com a cultura do brócolis, realizados em diferentes épocas do ano, visando estabilizar a variabilidade gerada pela presença de valores zeros nas múltiplas colheitas. Analisaram-se quatro experimentos com a cultura do brócolis utilizando a família de transformações de Box-Cox, com uma adaptação de Yamamura apresentada em 1999, devido a presença de valores nulos. Concluiu-se que para experimentos com brócolis a transformação mais adequada para as variáveis cabeças comerciais e não comerciais, e ramificações comerciais e não comerciais foi logarítmica para cultivos no inverno, na primavera e no verão. Para cultivos no outono, a transformação indicada para as variáveis cabeças comerciais e não comerciais e ramificações não comerciais foi "inverso da raiz quarta", enquanto para ramificações comerciais, "inverso da raiz quadrada". The major purpose of vegetable crops production systems is the profitable and economically viable yield of marketable products. Numerous field experiments with vegetable crops are carried out to determine biomass of weekly and heads production of marketable and non-marketable variables. However these variables possess the particular characteristic related to their presence or absence of the commercial structure of the plant at harvest time, what implicates in zero values for those variables, generate variability and affect variance analyses. This paper deals with the search of applicable transformations for variables studied in broccoli field experiments conducted in different planting times attempting to stabilize the variabilily resulting from the presence of zero values in multiple harvests. Due to the presence of zero values, broccoli experiments were analyzed using an adaptation of the Box-Cox transformation family found in Yamamura in 1999. The most adequate transformation found for marketable and non-marketable heads and side shoots of broccoli grown in winter, spring and summer was the logarithmical. For marketable and non-marketable heads and non-marketable side shoots for fall-grown broccoli the inverse fourth root and to marketable side shoots is a inverse square root was the indicated transformation.

The use of geostatistics requires at least that the intrinsic hypothesis be satisfied. The presence of a trend in the data invalidates this hypothesis. One of the ways of solving this problem is by subtracting a function fitted to the original data and working with the residuals. This technique also represents a change to a smaller scale of the variability and surface roughness. This paper describes the detrending technique of subtracting a trend surface fitted by the least squares method and discusses the results using topographical data as examples. The objective is to show how the detrending technique works for different scales and degrees of trend and how to interpret the results. It is shown that the simplest the surfaces fitted that does the work of removing the trend the best are the results obtained. The use of jack knifing is proved useful to validate the resulting semivariograms. For most of the applications and depending upon the scale, a linear or a parabolic surface works reasonably well. The back transformation of the data afterwards is very easily done by adding back the subtracted trend surface. O uso de geoestatistica exige que pelo menos a hipótese intrínseca seja satisfeita. A presença de tendência invalida esta hipótese. Uma das maneiras mais práticas de resolver esta questão é subtrair dos dados originais uma função ajustada por mínimos quadrados, trabalhando com a função residual resultante. Esta técnica representa uma mudança de escala da variabilidade e da rugosidade da superfície para uma escala menor. Este trabalho descreve a técnica da remoção da tendência pela subtração de uma superfície ajustada por mínimos quadrados e discute os resultados usando dados topográficos como exemplos. O objetivo é mostrar como usar esta técnica para remover tendências de superfícies de diferentes escalas e com diferentes graus de superfície e como interpretar os resultados. Foi mostrado que quanto mais simples for a superfície ajustada que resolve o problema de tendência, melhores são os resultados obtidos. O uso da validação cruzada provou ser útil para validar os semivariogramas resultantes. Para a maioria das aplicações e dependendo da escala, uma superfície linear ou parabólica funciona muito bem. A transformação de retorno nos dados é bastante fácil e é feita somando de volta a superfície subtraída.

O objetivo da pesquisa foi verificar a melhor época de aplicação de dessecantes, a fim de permitir a colheita de sementes de soja com a máxima qualidade fisiológica e sanitária. Assim, foi semeada a cultivar IAC-15 na área experimental da FE/UNESP - Campus de Ilha Solteira, localizada no município de Selvíria, MS. O delineamento experimental utilizado foi o em blocos casualizados, estando os tratamentos dispostos em esquema fatorial 3 x 3 e 4 x 4 de produtos e épocas de aplicação, nos anos agrícolas de 1996/97 e 1997/98 respectivamente. Os dessecantes utilizados no ano agrícola de 1996/97 foram o paraquat, diquat e mistura paraquat + diquat nas doses de 400, 300 e 200+150 g ha-1 respectivamente. Em 1997/98, foram utilizados os mesmos dessecantes, nas mesmas doses, acrescentando-se, nesse caso, mais um tratamento, ou seja, o produto glufosinato de amônio, na dose de 400 g ha-1. Como épocas, foram realizadas três aplicações em 1997 e quatro em 1998, todas em intervalos de cinco dias a partir do estádio R6. Nas condições ambientais em que se realizou a pesquisa, a melhor época de dessecação foi quando as plantas estavam com 80% a 90% de vagens com coloração amarela e marrom e teores de água nas sementes entre 45% e 60%. Com relação aos dessecantes, não se obteve, com qualquer dos produtos testados, potencial fisiológico e sanitário suficientes para a comercialização das sementes. The objective of this paper was to verify the ideal moment of application of desiccants on the soybeans crop, to obtain seeds with maximum physiological and sanitary quality. The cultivar IAC-15 was sowed at the experimental area of FE/UNESP - Campus of Ilha Solteira, located in the district of Selvíria, State of Mato Grosso do Sul (20º 22'S, 51º 22'W at approximately 335 m of altitude). The experimental design was a randomized block, with treatments in a factorial scheme of 3x3 and 4x4 (dessicant x application time), in 1996/97 and 1997/98, respectively. The desiccants applied during the season agricultural year 1996/97 were: paraquat, diquat, paraquat+diquat mix at the doses 400; 300; 200+150 e 400 g a.i.ha-1, respectively. In 1997/98 the same desiccants were used, at the same doses, with additional treatment application of ammonium glufosinate at the dose of 400 g a.i.ha-1. The desiccants were applied three times in 1996/97 and four times in 1997/98 with 5 days intervals starting at the R6 stage. According to the environmental conditions of this research the best desiccation time was when soybean plants had 80% to 90% of pods with yellow and brown coloration and seeds with 45% to 60% of water content. There were no effects of any of the desiccants tested in the physiological and sanitary potential required for commercialization of the seeds.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:19Z No. of bitstreams: 1 S0006-87051999000100017.pdf: 73800 bytes, checksum: 600a9f9b552f9dff346937020f8f5fa0 (MD5) Made available in DSpace on 2013-08-22T18:49:19Z (GMT). No. of bitstreams: 1 S0006-87051999000100017.pdf: 73800 bytes, checksum: 600a9f9b552f9dff346937020f8f5fa0 (MD5) Previous issue date: 1999-01-01 Made available in DSpace on 2013-09-30T19:39:38Z (GMT). No. of bitstreams: 2 S0006-87051999000100017.pdf: 73800 bytes, checksum: 600a9f9b552f9dff346937020f8f5fa0 (MD5) S0006-87051999000100017.pdf.txt: 15351 bytes, checksum: 28d5bfb4bbf8f6a950c6032a75046a00 (MD5) Previous issue date: 1999-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:10:31Z No. of bitstreams: 2 S0006-87051999000100017.pdf: 73800 bytes, checksum: 600a9f9b552f9dff346937020f8f5fa0 (MD5) S0006-87051999000100017.pdf.txt: 15351 bytes, checksum: 28d5bfb4bbf8f6a950c6032a75046a00 (MD5) Made available in DSpace on 2014-05-20T15:10:31Z (GMT). No. of bitstreams: 2 S0006-87051999000100017.pdf: 73800 bytes, checksum: 600a9f9b552f9dff346937020f8f5fa0 (MD5) S0006-87051999000100017.pdf.txt: 15351 bytes, checksum: 28d5bfb4bbf8f6a950c6032a75046a00 (MD5) Previous issue date: 1999-01-01 A circunferência de rolamento dinâmica dos pneus agrícolas é uma medida importante para o estudo do desempenho de tratores agrícolas. Neste trabalho, compararam-se dois métodos de determinação da circunferência de rolamento dinâmica - um manual e um eletrônico (com instrumentação das rodas de tração) - sob duas velocidades de deslocamento e cinco combinações de pressão de inflação nos pneus dianteiros e traseiros. O método manual forneceu valores estatisticamente superiores aos do eletrônico, com diferença absoluta máxima de 0,24%. A pressão de inflação influenciou significativamente os valores medidos, enquanto a velocidade de deslocamento, para os valores do ensaio (3,0 e 6,0 km.h-1), não apresentou influência significativa. The dynamic rolling circumference of agricultural tires is an important parameter to take in to account during agricultural tractor performance evaluation. Two measuring methods were compared in this paper, one manual and the other using electronic instrumentation of wheel drives. Two forward speeds and five combinations of front and rear tires inflation pressure were analyzed. The results showed that the manual method gave statistically higher values than the electronic one; although the maximum absolute difference had been of 0.24%. The inflation pressure presented significant influence in measured values, while the forward speed, for tested values (3.0 and 6.0 km.h-1), showed no significant influence. Instituto Agronômico Universidade Estadual Paulista Universidade Estadual Paulista

Modelos matemáticos agrometeorológicos que relacionam a fenologia, a bienalidade e a produtividade do cafeeiro, foram desenvolvidos e testados para Mococa (SP), a partir de série de dados de produtividade de cafeeiros adultos, variedade Mundo Novo, correspondente ao período de 1966/67 a 1973/74. Os modelos baseiam-se na penalização da produtividade potencial, em função da produtividade do ano anterior e das relações ER/EP (evapotranspiração real e potencial), derivados de balanços hídricos decendiais seqüenciais durante os estádios fenológicos, considerando 16 combinações diferentes. A penalização é feita à medida que haja restrição hídrica para a planta durante os diferentes estádios fenológicos, considerando coeficientes de resposta da cultura ao suprimento hídrico, incorporados numa função aditiva ou multiplicativa. O modelo com penalização aditiva apresentou melhor desempenho na parametrização dos coeficientes em relação ao multiplicativo. Os melhores ajustes entre dados observados e estimados foram obtidos com modelo aditivo que relaciona o fator hídrico durante os trimestres (combinação D1) jun./jul./ag.; set./out./nov. e dez./jan./fev., os quais apresentaram coeficientes de resposta da cultura ao suprimento hídrico (ky) de +0,38 (ky1), +0,61 (ky2) e +0,18 (ky3), respectivamente, para os estádios fenológicos da dormência das gemas/início do florescimento, florescimento/formação do grão e formação do grão/maturação. As magnitudes dos valores de ky1 e ky2 revelam que a produtividade do cafeeiro é particularmente sensível ao estresse hídrico durante os estádios fenológicos do florescimento e formação do grão. O teste do modelo apresentou boas estimativas, com coeficientes de determinação de 0,93 e índice de concordância (d) de 0,98. This paper describes a new method to reliably monitor and assess drought impact on coffee yields just before the beginning of the maturation growth stage. A good model requires the evaluation of the sensitive indices and test for a specific variety and region. Phenological and yield data for Mundo Novo cultivar were taken from experiments conducted at the Instituto Agronômico Experimental Station located in Mococa (lat. 21°28'S, long. 47°01'W, alt. 665 m), São Paulo State, Brazil, during 1967 to 1974. The models tested are based in the penalization of the crop yield potential according the previous yield and the ER/EP relation (actual/potential evapotranspiration), derived by 10-day soil water balance occurred during different growth stages. These ratios were weighted by derivation of crop phase yield-response coeficients (ky values) in additive and multiplicative type models. Based on the model's statistics, the additive type model presented better performance than the multiplicative one. The additive model which considers the crop phases combination D1: bud dormancy/ flowering beginning (Jun/Jul/Aug), flowering/grain formation (Sep/Oct/Nov) and grain formation/maturation (Dec/Jan/Feb) presented the best performance. An analysis of the ky values shows that this combination D1 gives higher weigth to the water relations during the flowering and grain formation (fruit set), with R2 of 0.93 and d-index agreement of 0.98.

A grande maioria dos ensaios de manejo e fertilidade do solo utiliza o método de delineamentos experimentais, segundo o qual as observações devem ser independentes umas das outras e as parcelas experimentais, uniformes quanto aos atributos estudados. A hipótese de independência entre as amostras apenas pode ser satisfeita e verificada na prática, se a amostragem contiver informações geográficas, como, por exemplo, as coordenadas com referências a um eixo arbitrário para possibilitar análises da geoestatística. O objetivo deste trabalho foi estudar a variabilidade espacial de alguns atributos químicos e granulométricos do solo dentro de uma parcela experimental e mostrar o uso da geoestatística para analisar os dados. O campo estudado localiza-se no Centro Experimental de Campinas do Instituto Agronômico, Campinas (SP), em um latossolo roxo distrófico sob preparo convencional nos últimos dez anos. Marcou-se uma parcela de 30 m por 30 m a cada 5 m em duas direções, resultando em um reticulado quadrado de 49 pontos de amostragem. Em cada ponto, coletaram-se amostras de solo das camadas 0-25 cm e 25-50 cm de profundidade, as quais foram levadas ao laboratório, secas ao ar, peneiradas em uma malha de 2 mm e submetidas às análises granulométricas e químicas de rotina para obter teor de argila, teor de silte, delta pH, soma de bases (S), capacidade de troca catiônica (CTC) e saturação por bases (V%). Para a análise de variabilidade espacial, utilizou-se a geoestatística. Os coeficientes de variação encontrados são mais altos na camada 0-25 cm do que na 25-50 cm, provavelmente devido à região de maior alteração com cultivo. Foi encontrada dependência espacial para todos os atributos analisados para a camada 0-25 cm, e dependência fraca para a camada 25-50 cm. Considerando que o campo engloba apenas uma área de 30 m por 30 m, conclui-se que a variabilidade encontrada para os atributos químicos do solo foi grande e que a amostragem ao acaso falharia em detectá-la e, por isso, esconderia a realidade.The majority of experiments on soil management and soil fertility uses experimental and statistical procedures which require statistically independent samples and uniform experimental plots. This hypothesis can only be satisfied and verified in practice with geostatistical calculations such as semivariograms. The objective of this paper was to study the spatial variability, within an experimental plot, and to show the use of geostatistical analysis. The field selected for this study is located at the Centro Experimental de Campinas, Instituto Agronômico, Campinas (SP), Brazil, on a Dusky Red Latosol, which had been on conventional tillage for the previous 10 years. A 30 m by 30 m plot was marked on a square grid of 5 m, resulting in 49 sampling points, in which bulk soil samples were collected at the depths of 0-25 cm and 25-50 cm, taken to the laboratory, air dried, sieved on the 2 mm sieve, and submitted to routine chemical and particle size analysis in order to obtain the clay content, silt content, delta pH, sum of bases, cation exchange capacity, and base saturation. Geostatistics was used for the spatial variability analysis. The coefficients of variation found indicate higher variability for all properties at 0-25 cm than at 25-50 cm, probably due to soil tillage depth. Spatial dependence was also stronger at 0-25 cm than at 25-50 cm depth. It was concluded that the spatial variability for the chemical properties was high considering the plot size of 30 m by 30 m and that random sampling would fail to detect it.

Este trabalho visa estabelecer um método que propicie a determinação do tamanho ótimo da parcela experimental, determinando o ponto de máxima curvatura por meio de cálculos algébricos. Há uma relação entre a variância da parcela e seu tamanho, como também entre o coeficiente de variação da parcela e seu tamanho. Mediante a apresentação e discussão de um exemplo, conclui-se que o método oferece uma solução algébrica para o ponto de máxima curvatura e não leva a interpretações diferentes quando se altera a escala do gráfico. Entretanto, pode apresentar um tamanho de parcela que corresponda a um coeficiente de variação ainda alto, revelando-se, então, desaconselhável. The objective of this paper was to determine a method to allow the determination of good experimental unit size, using the point of maximum curvature estimated, by algebraic calculus. There is an empiric relation between the coefficient of variation of experimental unit and its size. One example is presented and discussed to make possible the following conclusions: the method offers an algebraic solucion for the point of maximum curvature; the method does not permit different interpretations when the scale of the graph is dispossed differently; the method may present a size of experimental unit for high coefficient of variation, and in this case it is not recommended.

Para verificar se a pequena influência da heterogeneidade das variâncias, observada em trabalho anterior, sobre os testes de Bonferroni, "t" e Tukey se devia ao fato de ter sido utilizado o erro médio que corresponde ao quadrado médio da interação tratamentos x blocos (Q.M. trat x bloco), os autores estudaram o comportamento do teste "t" com o uso de três tipos de erro: Q.M. trat x bloco, erro do contraste específico e erro ponderado dos contrastes. Foram simulados 200 experimentos, em grupos de 50, para cada uma das 56 combinações de quatro coeficientes de variação, dois efeitos de tratamentos e sete grupos de heterogeneidade, totalizando 11.200 experimentos. Foi feita a análise da variância de cada ensaio e estudados os seguintes contrastes: m1 - m3 e m2 - m3, onde m3 representa a testemunha. "A priori" foi estabelecido que o tratamento 1 seria superior à testemunha nas quantidades de 8 e 17% (para os efeitos 1 e 2 respectivamente) e o tratamento 2, nas quantidades de 5 e 12% (para os mesmos efeitos). Assim, foi empregado o teste t, unilateral, para comparação das médias nos dois contrastes. Na presente pesquisa, são válidas as seguintes conclusões: as diferenças nas porcentagens de rejeição com os três tipos de erro praticamente inexistem; as relações de variâncias com valores maiores que 6 podem ser consideradas heterogêneas, quando utilizado o erro do contraste; a porcentagem de rejeição obtida é indiretamente proporcional ao coeficiente de variação e diretamente proporcional à magnitude dos contrastes, mesmo em condições de heterogeneidade de erros. It was observed previously a small effect of heterogeneous variances on the Bonferroni's test, Student "t" test and Tukey's test. In this paper, it was tested whether such observation was due to the fact that the error used for the tests was the treat. x block interaction mean square besides the existence of certain heterogeneous variances. The authors considered the existence of the following situations: a) two groups of variance in each experiment, and b) three kinds of errors for "t" test: treat. x block interaction mean square, specific contrast error for each comparison; and, pooled contrast error. It was simulated two hundred experiments, in groups of 50, for each of 56 combinations of four coefficients of variation, two treatment effects and seven groups of heterogeneous variances, performing a total of 11,200 simulations. In the analysis of variance, for each experiment, the following contrasts between means were considered: m1 - m3 and m2 - m3, where m3 represents the control treatments mean. The two treatment means m1 and m2 were considered "a priori" more productive than the control by 8% and 5% (effect 1) and by 17% and 12% (effect 2), respectively for m1 and m2. Thus, the one tail "t" test was applied. From the results observed, it was concluded that: a) non significant differences occurred concerning the percentages of rejections of the null hypothesis using any of the three errors considered; b) the relation among variances greater than 6 was statistically heterogeneous, when the error used was that of specific contrast error; and c) the percentages of rejections obtained were indirectly proportional to the coefficients of variation and directly proportional to the range values of contrasts between means, even in case of heterogeneous error conditions.

Realizou-se um ensaio de uniformidade na Usina Barra Grande, em Lençóis Paulista, SP, em 1982, a fim de estudar o tamanho e a forma de parcela para experimento de campo com cana-de-açúcar: simularam-se 55 diferentes tipos de parcela, cuja unidade básica constou de 2m lineares de uma linha de cana espaçada de outra de 1,5m, tomando-se o peso dos colmos de cada unidade básica. A formação de diferentes tamanhos de parcela foi feita pelo agrupamento das unidades básicas adjacentes. Foram determinados os índices de heterogeneidade do solo, b, cujos valores variaram de 0,2843 a 0,6000, dependendo dos métodos utilizados e da maneira de compor os blocos, parcelas e subparcelas. Em solos homogêneos, parcelas menores que 54m² podem ser utilizadas com maior eficiência na detecção de diferenças entre médias de tratamentos (d). Em solos heterogêneos, a variação do tamanho da parcela pouco influi no valor de d. Pelo método da curvatura máxima, parcelas de 6 a 12m² proporcionaram a maior diminuição no coeficiente de variação. Considerando uma mesma área experimental, existe grande vantagem em reduzir o tamanho da parcela e aumentar o número de repetições. Reduzindo a área da parcela para 12m², há condições de aumentar consideravelmente o número de repetições em experimentos com cana-de-açúcar. Isso significa maior possibilidade de detectar diferenças significativas entre as médias dos tratamentos. A influência do comprimento da parcela em reduzir o coeficiente de variação foi de 2,6 vezes maior que a da largura Para que diferenças de pequenas magnitudes entre tratamentos possam ser comprovadas estatisticamente, recomenda-se parcela de uma linha de 12m de comprimento, com doze repetições, ou duas linhas de 8m de comprimento, com oito repetições. As parcelas consideradas no presente trabalho são sem bordaduras. Uniformity trial with sugar cane was carried out in the Usina da Barra, at Lençóis Paulista, State of São Paulo, Brazil. Based on 1,512 yield data of sugar cane harvested in areas of 3.0m² (basic unit) or 1.5m by 2.0m, 55 different types of plots were simulated. The Smith's soil heterogeneity index, b, was estimated. Its values varied from 0.2643 to 0.6000, depending on the method employed or on the way of grouping blocks, plots and subplots. Using b = 0.6000 in a formula given by Smith, x= (b/(1-b)(K1/K2),an area of 6.0m² would give more information at lower cost. By the maximum curvature method the greatest reduction in the value of coefficient of variation occurs when the plot size varied from 6.0 to 12.0m². Presently, most plots used in sugar cane experiments range from 26.0 to 60.0m²; they are too large in relation to the best size obtained, that is, around 12m². There are practical advantages in using smaller plots and larger number of replications of treatments in an experiment, because the mean variance is inverselly proportional to the number of replications. Reducing the mean variances implies greater chance of detecting significant differences between treatment means. For homogeneous soils, smaller plots (12 to 36m²) may be used efficiently. In heterogeneous soils the plot size has little effect in the magnitude of the index d. The influence of the plot length, in reducing the coefficient of variation, was 2.6 times greater than the plot width. Therefore, in order to separate small differences between treatments, it is recommended the use of plots of one line 12m long with 12 replications per treatment or two lines 8m long with 8 replications. The plots considered in this paper are without guard rows.

In the State of São Paulo, coffee cherries, after harvesting, are usually put to dry, in the open or are artificially dried until reaching a percentage of about 18% of water. With this humidity, the coffee husks can easily be broken by rubbing the dried cherries in the hand. This operation is done before the coffee is stored. In this paper, are presented some preliminary data about the feasibility of storage-of coffee with more than 18% of water. The results of the experiments have indicated: a) in the Campinas enrivonment, coffee can be stored with about 24% of water-without loosing color and cup-quality; b) the storage with 24% of water reduces by 20-30% the drying operation and permits better condition for more uniforme coffee drying inside the hopper (tulha). Attention has also been called for the difficulty of establishing a practical method for determination of the point when the coffee cherries attain this higher percentage of water.

This paper presents preliminary results 01 chemical fertilizer experiments conducted at Campinas and Pindorama Experimental Stations on production of stems with leaves of the Murakami ramie (Boehmeria nivea) in two types of soils in the State of São Paulo. In CampiDas, on soil of the "roxa misturada" type, different effects of the treatments in the increasing of the production of stems with leaves have been found. In Pindorama, on soil oi the "Arenito Bauru" type, the results of experiment only showed a significant effect of phosphorus in increasing the production of stems with leaves.

Um método alternativo para arrancamento de cafeeiros é apresentado neste trabalho: consiste ele em uma garra arrancadora presa ao cafeeiro e tracionada por trator. Determinações realizadas no Centro Experimental de Campinas, em latossolo roxo, em fevereiro de 1984, demonstraram que o esforço médio requerido foi de 2.127 kgf por planta para C. canephora L. cv. Robusta e de 1.158 kgf por planta para C. arabica L. cv. Mundo Novo. Dentre os sistemas utilizados, o mais indicado foi o arrancamento de três cafeeiros sucessivamente, alinhados no sentido tratório em esforços independentes, numa só operação. Sua utilização propiciou menor movimento de solo do que no uso de trator com lâmina. Foi possível o emprego de um trator de pneus de potência de 100 cv. A new method for removing perennial plants is presented in this paper. It consists of using a clamp type of tool that is attached to a plant and pulled by a tractor. A study was conducted in Campinas, State of São Paulo, Brazil, in February of 1984 with a 12 year old coffee plantation on Dusk Red Latosol. The average effort required for coffee plants uprooting was 2,127kgf/plant for C. canephora L. cv. Robusta and 1,158kgf/plant for C. arabica L. cv. Mundo Novo. Among the several systems tested, the best was the use of three clamps applying individual effort in a successive remotion of three plants in one unique operation. This system had the advantage of smaller soil movement than the traditional use of bulldozer. The use of a 100hp wheel tractor was feasible for this system, and it presented a good performance of operation.

Procedeu-se à análise estatística para dados provenientes do uso de um delineamento de tratamentos central composto Box para três fatores, com níveis não eqüidistantes, através do estudo de uma superfície de resposta, utilizando um modelo quadrático em X, com dez parâmetros. São dadas as estimativas dos parâmetros beta, suas variâncias e covariâncias e o desenvolvimento da análise da variância, chegando-se ainda à equação em X, que possibilita a análise econômica dos ensaios. Resultados de um experimento de capim-swannee-bermuda, conduzido durante três anos em solo de cerrado, são analisados estatisticamente seguindo o esquema apresentado. The response of swannee bermuda grass (Cynodon dactylon (L.) Pers.) to nitrogen, phosphate and sulfur fertilization was studied. during three years, on a leached and phosphorus deficient "cerrado" soil. The experiment was conducted in four randomized blocks, using the treatment combinations specified in the Box composite design, but at non-equidistant levels (0, 1, 2, 4, 8); an extra point 000 was added, for economical reasons; the basic rates were 150, 100 and 20 kg/ha of N, P2O5, and S, respectively. The main objective of the present paper is to determine the response surface fitted to the data of the experiment, allowing, later on, the economical analysis of the results. A quadratic model with ten parameters was fitted to the annual data. Yijk= b0x0+ b1i x1i+ b1j x1j+ b1k x1k+ b2i x2i+ b2j x2j+ b2k x2k+ b1i1j x1i1j+ b1i1k x1i1k+ b1j1k x1j1k+ e ijk, where e ijk~ N(0, s²); b0= h0+ (b1i1j+b1i1k+b1j1k ); x1mt= -+Xmt and x2mt=- Xmt+ + X²mt, with m= i,j,k and t= 0, 1, 2, 4, 8. (The linear and quadratic components x1 and x2 are orthogonal.) The beta parameters were estimated through the least squares procedures; as the dosages were not equidistant, the sum of squares due to the regression was not available independently for each component. The coefficients of variation for the three years were 10,8%, 14,1%, and 9,1%, and the coefficients of determination wore 93,8%, 91,7% and 86,7% respectively. The general equation for the total of the period, including linear and quadratic year coefficients and their interactions with the b coefficients, was determined. The canonical equations showed negative signs for the l values; the point of maximum was outside the experimental regions. The X equations were given; so that the economical analysis of the experiment can be easily performed.

Foram instalados dois ensaios de cultivares de trigo, sendo um na Estação Experimental de Tietê, e o outro, na Fazenda Santa Isabel, município de Itaberá. Os cultivares IRN-526-63, Pitic-62 e IRN-152-63, de origem mexicana, não se adaptaram às condições adversas do sul do Estado (Itaberá), entre as quais destacaram-se: baixa saturação em bases, baixíssimo teor de fósforo e principalmente a influência do Al3+ trocável ocasionando "crestamento" nas plantas. Os cultivares IAC-10, IAC-7, BH-1146, IAC-9, S-33, IAC-11 e IAC-8 apresentaram tolerância a essa condição adversa. No ensaio de Tietê, onde o solo mostrou altos teores de K+ e PO4³ , bom teor de Ca2+ 4- Mg2+ , não apresentando alumínio livre, os cultivares IRN-526-63 e Pitic-62 desenvolveram-se normalmente, apresentando produções superiores às dos demais cultivares estudados. This paper presents the results of two cultivar trials on wheat (Triticum aestivum L.), carried out at the Tietê Experiment Station and at Santa Isabel Farm, Itaberá. The cultivars IRN-526-63, IRN-152-63 e Pitic-62, Mexican germoplasms, were very susceptible to "crestamento" at Itaberá soil, giving small yields. The Brazilian germoplasms showed tolerance to Al3+ , with average yields. At Tietê trial, IRN-526 and Pitic-62 cultivars showed good performance, having the most yield in this condition.

São apresentados resultados experimentais da produção de fôlhas em amoreiras de variedades comuns, durante o período de formação das mudas, com os sistemas denominados de cepo e fuste, em duas regiões, Limeira e Tatuí, do planalto paulista. Os resultados quanto à produção de fôlhas, em dois anos em cada região, permitiram as conclusões: Em Limeira, para a variedade Calabreza, o sistema de fuste foi muito superior ao de cepo. Para as variedades Fernão Dias e Lopes Lins, o sistema de fuste foi também superior, porém, de forma menos acentuada. Em Tatuí, no caso das variedades Calabreza e Fernão Dias, o sistema de cepo mostrou-se, ao contrário, mais produtivo. Para a variedade Lopes Lins, não houve diferença entre os dois sistemas de cultivo experimentados. In this paper the experimental results are reported on trials with leaf production carried out with common varieties of mulberry trees (Morus alba)during the period of seedlings formatioin by the systems known as "cepo" and "fuste", in two regions of the Paulista Plateau, namely Limeira and Tatuí. Regarding leaf production, in two years, for the regions, results allowed to reach the following conclusions: In Limeira, for the variety Calabreza, the system "fuste" showed highly superior to that named "cepo". As to the varieties Fernão Dias and Lopes Lins, the "fuste" system was also very satisfactory but not in a remarkable manner. In Tatui, as for the varieties Calabreza and Fernão Dias, the "cepo" system, on the contrary, showed to be more productive. Considering the variety Lopes Lins, there was not found any difference between the two tested cultivation systems.

Preliminary results are presented in this paper of an experiment with Morus albaL. designed for the purpose of leaf production and laid out as a factorial 33 experiment (Cochran - 2 replications), in which were studied three common varieties of mulberry trees : Calabreza, Fernao Dias and Lopes Lins, same being grown and shaped through the "cepo" system and planted in the three spacings 1.5 by 1.0, 1.5 by 1.5 and 1.5 by 2.0 meters, the pruning time having been in three different seasons, i. e., June 10, June 30 and July 20. The first crop year (1964/1965) proved that this trial, installed at the Experiment Station of Pindorama, of the Instituto Agronomico, showed the best production of leaves obtained with the variety Calabreza, when using the 1.5 X 1.0 m spacing and the latest pruning season, namely July 20.

São relatados os dados de ensaio de competição entre 16 cultivares de alho-porro (Allium porrum L.) procedentes da Europa e dos Estados Unidos da América do Norte, instalado em Campinas, em solo de formação glacial. O objetivo do experimento foi verificar o comportamento das variedades para o consumo in natura e para a indústria. Destacaram-se pela produção para consumo in natura as variedades I-3346 (Monstrueux D'Elbeuf) e I-3353 (Long de Nice), respectivamente com 3,8 e 3,3 kg/m², seguindo-se I-3351 (Monstrueux de Carentan), I-3460 (Doubouchet), I-3458 (Dubouchet de outra procedência) e I-3418 (Large American Flag) com 2,9 kg/m². Para indústrias, destacaram-se pelos maiores rendimentos as variedades I-3350 (Gros Long D'Été), com 12,9%, I-3353 (Long de Nice), com 12,2%, seguindo-se I-3351 (Monstrueux de Carentan), I-3458 (Dubouchet), I-3355 (Longo de Talos Grossos) e I-3349 (Bleu de Solaise). Não foi encontrada relação entre a produtividade (pêso do material in natura) e o rendimento em pó. Varieties of leek (Allium porrum L.), have already been sudied by the Seção de Olericultura of the Instituto Agronômico, using seeds imported from countries other than Brazil in view of leek not producing under our climatic conditions. Up to 1961, leek was cultivated in the State of São Paulo, only for fresh market because of the small demand. During the last years, its culture is growing more and more on account of the compensating prices reached on the market, the demand being high from important industries which devote themselves to the preparation of dry soups and flavours. In this paper data are given which were obtained from an experiment of competition with 16 varieties proceeding from Europe and the United States. It was installed in 1963 at the Central Experiment Station, in Campinas, on an area where the soil is of Glacial formation. The purpose of this trial was to determine which varieties are best for fresh market or for the industry. Among the 16 varieties were best for fresh market: Monstrueux D'Elbeuf (I-3346, yielding 3.8 kg per square meter, I-3353, Long de Nice with 3.3 kg/sq.m., seeds imported from Vilmorin-Andrieux S. A., France. Followed by - Monstrueux de Carentan I-3351, Dubouchet I-3460, wiht 3.0 kg/sq.m., from the same Seed Company, Dubouchet I-3458, supplied by the Companhia Industrial e Comercial Brasileira de Produtos Alimentares, and Large American Flag I-3418 from the Asgrow Seed Company yielding 2.9 kg/sq.m. For the industry purpose the following were best: Gros Long D'Eté I-3350, with 12.9% of dry matter, Long de Nice I-3353 with 12.2%, the two from the Vilmorin-Andrieux S. A. Followed by Monstrueux de Carentan I-3351, 11.9% from that same Seed Company, Dubouchet I-3458, 11.5% supplied by Companhia Industrial e Comercial Brasileira de Produtos Alimentares, Longo de Talos Grossos I-3353, from Casa Corradini de Sementes, São Paulo, 11.4% and Bleu de Solaise I-3349 from France, 11.2%. Considering the studies carried out, there was no relation found between the productivity-weight of the vegetable for fresh market and the percentage of dry matter.

No presente trabalho são relatadas experiências com 16 variedades de amendoim (Arachis hypogaea, L.), recebidas dos Estados Unidos da América do Norte, do Congo Belga e de várias regiões do Brasil. Essas experiências, em número de oito, das quais três pertencentes à décima série (ano agrícola de 1953/54) e cinco compreendendo a décima-primeira série (ano agrícola de 1954/55), foram executadas nas localidades de Campinas, Ribeirão Prêto, Pindorama, Presidente Prudente e Tatuí, no Estado de São Paulo. Os resultados obtidos mostraram que, para as condições em que foram realizados os ensaios, as variedades Paulista-269, Bandeirante-263, Brasília-265, Centenário-264 e Tatuí-76, sobressairam-se das demais, notadamente a primeira, que, de um modo geral, foi bem classificada em todas as localidades, não só em relação à produção como pelo alto teor em óleo, nos frutos. A variedade Tatu-53 (testemunha), ainda bastante cultivada no Estado, classificou-se entre as piores. As maiores produções foram obtidas em terra arenosa. Nas terras roxa e roxa-misturada, também se conseguiram boas produções. Já na região representada pela terra massapê as produções foram fracas, confirmando os resultados dos anos anteriores. This paper reports the results obtained from field tests with sexteen peanut varieties received from the United States of America, Belgium Congo and several Brazilian regions. Eight experiments were conducted in the following counties of the State of São Paulo: Campinas, Ribeirão Preto, Pindorama, Presidente Prudente and Tatuí. Yield data showed the varieties Paulista-269, Bandeirante-263, Brasilia-265, Centenário-264 and Tatui-76 to prove better, particularly the first one, that ranked good classification in every locality as far as seed production and oil content of the seeds are concerned. Variety Tatu-53 which still widespreads all over the State, was one of the least yielders. The highest yields were obtained on sandy soils. On "terra-roxa" or "terra-roxa-misturada" soils, high production levels were also obtained; on the "massapé" soil the harvest was poor, thus ratifying prior results.

Quatro distâncias entre as mudas na mesma cova foram estudadas, com a finalidade de determinar quais as mais indicadas para a plantação de um cafèzal em terra anteriormente ocupada por culturas diversas. O presente ensaio foi instalado em solo tipo terra-roxa-misturada, na Estação Experimental Central em Campinas e compreende as distâncias de 10, 20, 30 e 40 cm entre as quatro mudas plantadas numa mesma cova. Os resultados obtidos dizem respeito às quatro primeiras colheitas. Diferentes observações foram feitas, dando as seguintes indicações: 1) quanto ao desenvolvimento das plantas, indicou a análise estatística das alturas correspondentes à terceira medição: a) haver diferenças entre as alturas médias das plantas nas covas, dentro dos canteiros, as quais são da mesma ordem para os diferentes tratamentos; b )os cafeeiros plantados a 10 e 20 cm nas covas, apresentam, em média, plantas mais altas, e os plantados a 30 e a 40 cm, mais baixas; a diferença entre os dois grupos é significativa e de ordem menor que 10%; 2) as produções estudadas mostram um aumento linear de acordo com o aumento do espaçamento entre as plantas na cova, estatisticamente significativo: 3) as diferenças entre as peneiras médias dos diferentes tratamentos são pequenas, indicando, portanto, não haver influência das distâncias no tamanho das sementes. Coffee plantations in Brazil are usually made with four seeddlings per hill. To study the problem of spacing the seedlings in the hill, an experiment is being carried out at the Estação Experimental Central of the Instituto Agronômico in Campinas in the "terra-roxa-misturada" type of soil. Four square spaciugs between the seedlings were compared: 10, 20, 30 and ±0 cm. Yield data and other observations reported in this paper refer to the first four harvests. The following results have been so far recorded: 1. Measurements of the seedlings made at three different times indicated that there was a significant statistical difference between plants in the same hill, and that seedlings set 10 or 20 cm apart were higher than those planted at 30 or 40 cm. 2. The statistical analysis of yield data showed a significant linear increase related to the increase in spacing between seedlings in the hill. 3. Variations in the spacing between seedlings in the hill did not affect the size of the coffee seeds.

Neste artigo são relatados quatro grupos de ensaios, compreendendo 32 resultados anuais, nos quais o desbaste, na cultura do algodoeiro, foi efetuado desde 15 até 80 dias após a emergência das plantas. Na maioria dêsses ensaios, que foram conduzidos entre 1927-28 e 1943-44 em diversas localidades do Estado de São Paulo, à medida que se retardou o desbaste as produções de algodão em caroço decresceram consideràvelmente, apesar de terem os «stands» melhorado um pouco; a precocidade e o tamanho dos capulhos diminuiram apreciàvelmente, ao passo que a porcentagem de fibra e o comprimento desta sofreram apenas reduções muito pequenas. Em alguns ensaios também foram estudadas outras características das plantas e da produção. Do presente estudo os autores concluíram que, na cultura em apreço, o desbaste deve ser efetuado 20 a 30 dias após o nascimento das plantas. In this paper the authors study four groups of experiments, comprising a total of 32 annual results, in which the time of thinning cotton varied from 15 up to 80 days after the emergence of the plants. The experiments were conducted between 1927-28 and 1943-44 and located at several places of the State of São Paulo. On the average, as thinning was delayed the stands became a little better, but the yields of seed cotton decreased considerably; while the lint percentage and length diminished slightly, the bolls' size and the contribution of the first picking to the final yields suffered appreciable reductions. The authors conclude that cotton should be thinned 20 to 30 days after the emergence of the plants.

SUMMARY 1) The present paper represents a continuation and complement to a previous publication (Brieger 4) in which I explained the mathematical relations between the four most important types of chance distributions. While carrying out a large number of statistical analysis, of genetical and agricultural experiments, I came to the conclusion that the existing tables for the limits of chance distributions (Fisher and Yates, 7, Snedecor, 8, Brieger 2) are not satisfactory in three repects. a) The tables of Fisher and Yates and of Snedecor give the limits of the t-test and of the z or F-test with different systems of ordinates ; b) there are only tables for bilateral limits of t (Student) and for unilateral limits of z (Fisher), F (Snedecor) or theta (Brieger) ; c) the tables contain only values for a limited number of degrees of freedom without an auxiliary table for interpolation. The tables, included here, are calculated in such a way as to avoid these objections. 2) The basic value for all of the new tables is the relative deviate ,which may be either simple or compound : A simple relative deviate is the quotient of a difference between a variate and its ideal value which generally is the mean divided by the respective standard error. When comparing several deviates simultaneously, we unite them in one balanced mean estimate which is the square root of the mean square deviate (the sum of the squares of deviates divided by their degree of freedom). This value divided by the best estimate of the respective standard error is the compound relative deviate. The four main types of chance distributions may be defined mathematically in such a form that the relative deviates form the abscissa and their frequencies the ordinates, as shown in the preceding publications (Brieger 4). Simple relative deviates follow Students' distribution when the degree of freedom of the divisor is small (t-test) and the Gaussean distribution (delta-test) when the degree of freedom is infinitely large, accepting as a reasonable aproximation to infinity a value bigger than 100. Relative compound deviates, on the other side, follow either Fisher's or Pearson's distribution, when the degree of freedom of the dividend is bigger than one and that of the divisor is either a limited or unlimited value (theta-test). 3) I explained (4) in

Com o objetivo de estudar a adubação do arroz de sequeiro, foram instalados cinco ensaios na variação Lins dos Solos Podzolizados de Lins e Marília, escolhendo-se os locais de acôrdo com o teor de fósforo. Utilizou-se ocultivar 'Pratão' e o delineamento fatorial 3³ para N, P e K, acrescentando-se um tratamento extra com microelementos. Sòmente em uma localidade houve reação ao nitrogênio. Houve forte reação à adubação fosfatada, mostrando-se a aplicação de 60 kg/ha de P2O5 suficiente para atingir o máximo de produção. Os locais em que o teor de PO4-³ solúvel em H2SO4 0,05 N no solo era igual ou maior que 0,08 e.mg por 100 g de terra, não mostraram efeitos benéficos da adubação com fósforo. O potássio induziu aumentos de produção em apenas uma localidade. A mistura de microelementos não proporcionou acréscimos de produção em quaisquer dos ensaios. Upland rice is one of the principal cultures in the State of São Paulo. However, there is no doubt that the productivity of this crop is low. Among the problems that are responsible for this low productivity is the lack or deficient use of fertilizers. The N, P, K and microelements were then considered. The present paper shows the results of five fertilizer experiments with upland rice, in which the cultivar 'Pratão' was used. The scheme was a factorial 3x3x3 with an extra treatment for microelements and the experiments were installed on Podzolized Soils on Calcareous Sendstone Lins variation. Through chemical analysis of a great number of soils, the places were chosen. For this purpose special consideration was given to the e.mg PO4-³ per 100 f of soil content. Nitrogen only affected the production in one place, in which the plant residues of corn were incorporated in the soil. Under 0.08 e.mg PO4-5 per 100 g of soil, phosphorus affected the production of rice. The use of 60 kg/ha of P2O5 was sufficient for the higher yields. The use of potassium was efficient in only one place. No beneficial effect was noted with the use of microelements.

Há muito tempo que o Instituto Agronômico vem realizando experiências para determinar a eficiência relativa de vários fosfatos na adubação do milho. Como até agora só foram publicados os resultados obtidos em algumas delas, os autores resolveram relatar, em séries, os que ainda se acham inéditos. No conjunto desta primeira série, constituída de seis ensaios iniciados até 1940-41 e cujos planos variaram consideravelmente, em regra superfosfato e Renânia-fosfato se mostraram equivalentes e foram superiores a farinha de ossos crus, farinha de ossos degelatinados, escórias de Thomas, Serrana fosfato, Cibrafosfato e Rofosfato. Em um ensaio, .superfosfato e Renánia-tosfato loram bem inferiores a farinha de ossos degelatinados; mas esta, por sua vez, ficou praticamente sem efeito em outro ensaio, no qual os dois primeiros adubos deram resultados satisfatórios. Superfosfato granulado, que figurou em dois ensaios, foi um pouco superior ao produto comum em um deles e muito inferior no outro. Rofoscal, estudado em um ensaio, não aumentou a produção. Todavia, tis autores advertem que o pequeno número de ensaios deste grupo e as condições em que eles foram conduzidos não permitem tirar conclusões seguras, o que se procurará fazer após a publicação das outras séries. The relative efficiency of various phosphorus fertilizers for com has been tested in lhe Instituto Agronômico for many years. In this paper the authors report the results obtained in the first series consisting of six experiments started before 1941. As a whole, ordinary superphosphate and Rhenania phosphate gave similar results and were superior to Thomas slag, bone meal, Serranaphosphate, Cibraphosphate and Rophos-phate. Granulated superphosphate, which was included in two experiments, was a little superior to the ordinary product in one and much inferior in the other. Rofoscal, studied in one trial, did not increase the yield. The authors warn, however, that the small number of experiments and the conditions under which they were conducted do not as yet permit to draw definite and detailed conclusions. This will possibly be done after reporting the next series of experiments.

This paper presents various method used to evaluate the number of replications that guarantees the detection of prefixed differences with certain probabilities. The methods due to Neyman et al., Cochran & Cox, Harris, Horvitz & Mood, Tang, and finally the method due to Tukey, are presented with examples. Implications and limitations of these methods are also considered. A avaliação do número de repetições necessárias para a obtenção de resultados significativos, a partir da fórmula da diferença mínima significativa, não é satisfatória. Por êste processo os resultados serão significativos em cêrca de 50% dos futuros experimentos. São discutidos vários métodos que procuram eliminar êsse inconveniente: os métodos devidos a Neyman, o de Cochran e Cox, o de Harris, Horvitz e Mood, o devido a Tang e, finalmente, o de Tukey; consideram-se os casos em que a maior ênfase está no teste de significància e os casos em que o objetivo está na determinação de um intervalo de confiança de tamanho especificado. As condições necessárias para que cada um dos métodos possa ser corretamente aplicado e ainda, as limitações dos mesmos, são discutidos no texto. Transcreveram-se com a permissão dos autores, algumas tabelas, as quais facilitarão a aplicação dêsses métodos por parte dos experimentadores

1 - A presente contribuição refere-se aos trabalhos iniciais para o estabelecimento, na Estação Experimental de Limeira, de experiências sobre cavalos para as principais variedades cítricas comerciais no Estado de São Paulo, isto é, as laranjas Baianinha e Pera e o pomelo Marsh-seedless. 2 - Nessas experiências estão em estudo 12 variedades-cavalo pertencentes a 2 gêneros e 8 espécies. 3 - Ligeiras referências são feitas sobre as 12 espécies e variedades-cavalo, algumas das quais ainda não foram utilizadas no Estado, para tal fim. 4 - Citam-se dados sobre o número de sementes, germinação, poliembrionia e desenvolvimento relativo na sementeira. 5 - O desenvolvimento no viveiro, antes e depois da enxertia, se baseia em medições feitas de tempos a tempos, a princípio nos cavalos (altura) e depois nos cavalos e enxertos (circunferências da haste). 6 - As últimas medições feitas no viveiro, mostram que há comportamento significantemente diferente entre as 12 espécies e variedades-cavalo experimentadas, considerando-se os seus respectivos desenvolvimentos. 7 - No viveiro sobressaíram, por mais rápido crescimento, as seguintes espécies e variedades-cavalo : lima da Pérsia, limão rugoso, limão cravo, limão ponderosa e cidra. O trifoliata, as laranjas lima e caipira, e a tangerina cravo foram de crescimento mais lento, enguanto as laranjas azeda e agro-doce e o pomelo ocuparam posição média. 8 - Instalou-se a experiência definitiva com a transplantação das mudas, em 1936, para o lugar definitivo (pomar), formando-se 6 quadras (4 blocos e 24 parcelas cada uma). 9 - O plano destas experiências comporta observações sobre : a) Desenvolvimento das plantas b) Produção (frutos) qualitativa e quantitativa c) Suscetibilidade a moléstias e pragas d) Interação entre cavalos e enxertos e) Longevidade das plantas.1 - The present paper deals with the first results of an extensive study on the relations between stock and scion in Citrus, in progress at the Experiment Station of Limeira, of the Instituto Agronômico of Campinas, São Paulo, Brazil, since 1933. 2 - All the scions used belong to three commercial varieties : Baianinha (orange, derived from "Washington Navel"), Pera (orange, similar to Valencia) and Pomelo (grape-fruit "Marsh-seedless") were collected in each case from one individual of each type. 3 - The following 12 stock were studied : Laranja azeda (sour orange) Laranja agro-doce (bitter sweet orange) Laranja caipira (sweet orange) Laranja lima (sweet orange) Tangerina cravo (tangerine) Limão cravo (Rangpur lime) Limão rugoso (rough lemon) Limão ponderosa (ponderosa lemon) Lima da Pérsia (sweet lime) Pomelo (grape-fruit Triumph) Cidra (citron) Trifoliata (Poncirus trifoliata). All plants obtained came from seeds of one tree of each type, from unprotected flowers however. 4 - Data referring to the number of seeds per fruit, germination, polyembriony and classification according to size are given (quadro I). The mean height of the plants obtained after 6 months and 2 years nursery are to be found in quadro II. 5 - Twelve hundred individuals of each root stock were selected according to their uniform development, in accordance with Webber (25) and on 40 of each buds of the three scions were grafted. As measure of the development the circumference of the stock at a height of 20 cm and that of the scion at a height of 40 cm were used (quadros IV to IX). 6 - An analysis of variance "between" and "within" root stocks (quadro VI) showed in all cases a significant high variation "between" stock. In all cases, the scions were thinner than the stocks (quadro IX), the indices scion-stock varying from ca. 0,5 to 0,8. The respective means are to be found in quadro IV and V. 7 - There is also a consistent and significant difference between scions as shown by the values in quadro VII. 8 - A comparison between quadro VIII (not budded root stock) and quadro IV (budded) shows that generally the former grow better. They are however some exception to this rule, especially in "Tangerina cravo". 9 - All the observation reported so far were made in the nursery, but the detailed lay-out of the experiment in the orchard is also described. Lots of 4 or 9 plants of each combination were arranged in four complete random replications. The trees supported the planting out very well, only Citron replantings being necessary. The trees are now fully matured and produced already during 3 years. The results of the first five years of the experiment with trees in the orchard, including the analysis of their yields, will be given in a future publication.

This paper describes the results of superimposing certain types of 5 x 5 latin squares on a wheat uniformity trial. The purpose was to investigate the bias in the estimate of error when certain systematic squares (knight's move and diagonal) are chosen and to compare the results under conditions in Brazil with those obtained by Tedin in a similar investigation. The following conclusions are drawn : a) when latin squares are chosen by a random process, as recommended by Fisher, the observed distribution of the variance ratio of "treatments" compared with error is i n agreement with that given by theory; b) the estimation of error variance is biased when systematic squares are employed. In agreement with Tedin, we find that the knight's move square furnishes an overestimate, and the diagonal square an underestimate of error variance. The results show that, under the conditions of our trial, the systematic squares suffer from the same disadvantages which have been noted elsewhere.

At the Central Experiment Station «Theodureto de Camargo», in Campinas, since 1941, as well as at the Experiment Stations of Monte Alegre do Sul and Jundiai, starting 1952 and 1964, respectively, 49 cultivars were studied and nearly 2,000 «seedlings» obtained from crossings made in the three localities, and also from imported «seeds». In this paper the results of trials made in 1965 at the Experiment Stations of Monte Alegre do Sul and Jundia! are presented. In all of them, variety «Dr. Morere», also known as «Comum», formerly the most cultivated in the State of Sao Paulo, was used as check plant. At the Experiment Station of Monte Alegre do Sul, 9 varieties were studied. The total yield from July up to December and also the partial one of July-August was studied at a time when prices of strawberry are at the highest, because harvest begins then and also because fruits are bigger. The statistical analysis of data obtained, showed the following results: a) concerning the total yield, cultivar Monte Alegre, without differing from cultivars Camanducaia, Hybrid IAC-3592, Hybrid IAC-3432, Campinas and Hybrid IAC-2747, was superior to all the others (Hybrid IAC-2746, Hybrid IAC-3431 and Dr. Morere) on the level of \%;b) considering the partial yield, cultivar Monte Alegre was superior to all the others to the level of 5% and cultivar Campinas IAC-2712 was superior on the same level, only with regard to variety Dr. Morere or «Comum». At the Experiment Station of Jundiai, the following 5 cultivars entered the competition trial; Monte Alegre, Campinas «Comum». The yield of June up to December was studied and that of June to August as well, the following observations having been made: a) with regard to total yield, Monte Alegre was superior to all the others on the level of 5%; concerning productivity, variety Dr. Morere or «Comum» was inferior to all others on the level of 1%; b) as to partial yield, Monte Alegre nad Campinas with no differences between them, were superior to the Hybrid IAC-2747 and «Comum» on the level of 5%. The yields of the same varieties were better at the Experiment Station of Jundiai, where the acidity of soil, pH = 5.40, which is the best for strawberries, might have influenced. On the other hand, the soil at the Experiment Station of Monte Alegre do Sul showed an acidity equal to 4.30, which is harmful to the plant.

No período de 1946 a 1950 foram conduzidas duas experiências era Tupi Paulista e três em Mococa, para estudar o efeito, sôbre a produção da batatinha (Solarium tuberosum L.), da adição de farelo de cacau a adubações minerais contendo 40-120-60 e 80-120-60 kg/ha de N-P(2)0(5)-K(2)0. O farelo em apreço, que é um dos subprodutos da indústria do chocolate e consta principalmente de películas das amêndoas (sementes) de cacau, foi adicionado em doses que variaram entre 255 e 1100 kg/ha. A adição de farelo deprimiu um pouco a produção em Tupi, sendo que a depressão foi maior no tratamento que recebeu a menor dose de nitrogênio; em Mococa seu efeito foi positivo e apreciável na presença de 80-120-60, mas praticamente nulo quando adicionado a 40-120-60. Isso parece indicar que, na sua decomposição, o farelo deprimiu as disponibilidades do solo em nitrogênio assimilável. Assim, para estudar a conveniência de sua adição, dever-se-ía empregá-lo com bastante antecedência ao plantio; para aplicá-lo ao ser este efetuado, como nas experiências relatadas, o farelo deveria ser previamente curtido. This paper reports the results obtained in five experiments conducted from 1946 to 1950 and designed to study the effect of the addition of cocoa-shell meal to mineral fertilizers supplying 40-120-60 and 80-120-60 kilograms of N-P(2)0(5-)K2O per hectare. The mentioned meal, which is a by-product of the cocoa industry and consists essentially of the shells of the cocoa beans, was applied at rates varying from 255 to 1,100 kilograms per hectare. Two of the experiments were located at Tupi Paulista and the other three at Mococa, State of São Paulo. On the average, in the Tupj experiments the addition of cocoa-shell meal reduced slightly the potato yields, the reduction being greater in the presence of the fertilizer containing the smaller quantity of nitrogen; at Mococa it increased appreciably the yield in the presence of 80-120-60, but was ineffective when added to 40 120-60. Apparently these results indicate that, during its decomposition, the cocoa-shell meal depressed the available nitrogen of the soil. To study the advantage of its addition as organic supplement to mineral fertizers, the cocoa-shell meal should be applied some time in advance of planting; for the aplication immediately before planting, as in the experiments reported, it should be previously composted.

No presente trabalho são apresentados osresultados do estudo da produtividade individual de 4337 seringueiras, com cêrca de 37 anos de idade, plantadas de sementes no seringal Imperial, Óbidos, Estado do Pará. Além de sua capacidade de produção, foi também estudado o desenvolvimento das plantas (circunferência do tronco) e, ainda, as relações existentes entre produção e desenvolvimento e as seguintes características da casca das seringueiras: a) textura: lisa ou rugosa. pelo seu aspecto); b) dureza: mole ou dura, determinada pela resistência oferecida ao corte pela faca Jebong; c) côr: branca, vermelha ou rosada; d) espessura: fina ou grossa, a ôlho, pela espessura observada no corte, por ocasião de uma sangria. A análise dos dados permite verificar estreita relação entre o desenvolvimento das plantas e sua produtividade, sendo esta tanto maior quanto maiores são as plantas. Por outro lado, venfica-se serem mais produtiva- e de maior desenvolvimento as seringueiras com casca rugosa, dura ou grossa e, conseqüentemente, menos produtivas e menores as com casca lisa, mole ou fina. Observa-se, também, que associações de duas ou mais das características tidas como favoráveis à produção, dão em resultado ainda uma maior produtividade às plantas que as possuem, e que de associações semelhantes, de características tidas como desfavoráveis, resulta muito pequena produção por parte das plantas suas portadoras. O mesmo é verdade, em línhas gerais, no que se refere ao desenvolvimento das plantas. A côr da casca pouca ou nenhuma influência parece ter na produção e desenvolvimento das seringueiras.In this paper are presented the results of tapping 4337 seedlings of rubber trees (Hevea brasiliensis Muell.-Arg.) approximately 37 years old. The tapping system used was one full-spiral cut every fourth day, the cut made at an angle of 30º counter clockwise downward. Besides the production also were studied the size of the plants (measurement of the circumference of the trunk at one meter above the soil) and the following characteristics of the bark: a) texture: smooth (L) or rough (R), determined by its aspect; b) hardness: soft (M) or hard (D), determined by the resistance offered to the cut with a Jebong knive; c) color: white (B), red (V) or rose (Ro); and d) thikness: thin (F) or thick (G). delermined visually at the moment of a cut. A detailed discussion of the findings are presented and the results show a close relation between size of the plant (girth) and production, the yield increasing with the increase of the size of the plants. On the other hand it was observed that the better yielding plants were of greater size and with rough, hard and thick bark; consequently the poorer yielders were plants of small size and with smooth, soft or thin bark. Is was observed also that of the association of two or more of the characteristics of the bark apparently linked to better production, resulted in a greater productivity, and vice-versa. The color of the bark do not seem to be closely related to production. It is suggested that the bark characteristics may be used in studies related to selection and improvement of the rubber tree. The study of the population of plants shows also that: a) 10% of the plant population yielded 27.82% of the total latex production: b) 25% of the plant population yielded 49.27% of the total latex production: c) 50% of the plant population yielded 73.51% of the total latex production: d) 75% of the plant population yielded 90.40% of the total latex production.

Com o objetivo de estudar a aplicação do sulfato de amônio em cobertura, em cultura de arroz (Oryza sativaL.), foi conduzido o presente experimento, em solo argiloso de várzea, da Estação Experimental de Pindamonhangaba, no Vale do Paraíba. Estudou-se, ainda, o efeito de doses crescentes de nitrogênio e de fósforo. Estudaram-se cinco níveis de nitrogênio, três de fósforo e sòmente um de potássio. A variedade foi a Iguape-agulha, e a cultura foi irrigada por inundação, como de hábito na região. Os resultados obtidos indicam grande eficiência da aplicação do sulfato de amônio em cobertura, quando efetuada entre os 30 e 50 dias após a germinação. As respostas encontradas para níveis de nitrogênio foram lineares e significativas, indicando que, nas condições do ensaio, mesmo a aplicação de 120 kg/ha do elemento ainda foi eficiente no aumento da produção. Não foi observada reação alguma à adubação fosfatada. This paper reports about an experiment carried out in argillaceous soil of lowlands, located at the Experiment Station of Pindamonhangaba, in the Paraiba River valley, and had in view the study of application of ammonium sulfate as top dressing, in rice crops. This same trial had further the purpose to find out which were the necessary doses of nitrogen that led to major production as well as the levels of phosphorus required for a good development and good yield of rice. The experimental lay-out used was that of ransom blocks where 5 doses of nitrogen were applied, 3 of phosphorus and one only of potassium. The variety of rice (Oryza sativa) used was the Iguape Agulha the culture being submitted to flood irrigation, which is the type common to the rice crops in that region of the State. The results obtained indicate the great efficiency toward increase of yield by application as top dressing of the ammonium sulfate. This fertilizer should be applied in the period between 30 and 50 days after germination. Responses determined by the doses of nitrogen were linear and significant, indicating that under the conditions of the trial, even the application of 120 kg per hectare of the element was still efficient for the increase of production. As for the phosphorous fertilizer no reaction whatever was observed.

No presente artigo apresentamos a análise da covariância de um látice retangular simples, com duas repetições de cada grupo básico. Os dados estudados representam a produção, em gramas, de algodão em caroço por canteiro, de uma experiência de comparação de linhagens. A análise estatística é apresentada com detalhes de forma a servir de modelo ao melhorador de plantas que queira se utilizar da covariância, para aquele tipo de delineamento. Também é apresentada a equivalência entre as duas notações, a usada no presente artigo e a mais usualmente encontrada na literatura, para o cálculo de látices retangulares simples. This paper describes the different steps taken in the covariance analysis for a simple rectangular lattice. The data are expressed as grams of seed cotton per plot from two replications each of the x and y groups of a 7 x 8 simple, rectangular lattice design. This experiment was carried out by the Secção de Algodão do Instituto Agronômico de Campinas.

No presente trabalho são relatados os resultados de sete anos de um estudo feito sob a forma de ensaio de campo com a finalidade de verificar o possibilidade pratica da restauração de lavoura velha de café, no Estado de São Paulo, mediante o emprego da irrigação associada a outras práticas culturais. Foram estudados os efeitos da irrigação, inicialmente em diferentes dosagens, e os efeitos das combinações fatoriais de NPK (duas dasagens), presença e ausência de estêrco de curral, e presença e ausência de adubação verde intercalar, utilizando o delineamento de blocos ao acaso com canteiros subdivididos, com um total de 8 blocos, cada um com 8 tratamentos de 16 plantas, totalizando 2.856 árvores, inclusive as bordaduras, abrangendo a área total de 35.000 m². A adubação química completa, parcelada, foi empregado como adubação básica, figurando a dosagem simples de NPK como testemunha; as adubações orgânicas foram testados como complementares. O ensaio foi instalado num dos melhores talhões de cafèzal velho da variedade Bourbom Vermelho, plantado há mais de 30 anos, em terra de tipo arenito Bauru, desbravada de mato virgem, na Estação Experimental de Pindorama, do Instituto Agronômico do Estado de São Paulo. As análises da variância dos dados de produção revelaram que o efeito da irrigação foi significativo apenas na colheita de 1957, com um aumento de produção da ordem de 90%. Apesar do elevado aumento de produção, o significando estatística não ultrapassou o nível de 5%, devido o irregularidade dos produções dos blocos. This paper reports and discusses results refering to a field trial set up to study irrigation and fertilization problems of old coffee groves. The seven year study, started 1953, was carried at a representative well coffee grove of Bourbon variety, about 35 years old, located in a typical sandy soil of the Bauru superior formation of the Pindorama Experiment Station, considered to well represent on extensive port of that formation where the bulk of coffee is at present produced in the State of São Paulo. Eight randomized blocks were used with a 2x2x2 factorial for the small treatments in each block, the following treatments being compared: complete chemical fertilizer in two dosages, with and without organic manure, with and without green manure as an annual intercrop. The irrigation treatments, the first two years, included application of 1 and 2 inches of water every three weeks, starting July, 2 inches storting August and no irrigation. The remaining 5 years the treatments compared were simply with irrigation and no irrigation. Irrigation application time was then mostly determined by soil moisture depletion, when about 50 millimeters were consumed from the 0-80 centimeter soil layer. Irrigation effect was significant only one year, with substantial increase in yield. The first two years irrigation apparently decreased yields. However, this result can be attributed to the effect of insufficient number of replications and to the fact that the blocks with no irrigation were benefited by their particular location in the field, where soil fertility was higher. The remaining years, although a balanced re-sampling was made to double the replications by reducing the irrigation treatments, the climate was generally more favorable to coffee production, thus minimizing the effect of irrigation. The use of green manure as an annual intercrop was shown to significantly decrease yields, in spite of the fact that seeds were inoculated and there was a basic substract of chemical fertilizer in all plots. The use of organic manure in the dosage of about 12 kg every year per coffee tree (which means o group of 3-6 trees originally planted in the some hole) did not increase yields. In no year the effect of double dosage of fertilizer was significant. The average basic dosage used was the following per tree per year: 311 g of ammonium sulphate (20,5% N), 162 g of calcium superphosphate (20% P2O5) and 145 g of potassium chloride (60% K2O). When yields of the treated plots were compared with yields of untreated border plot trees, it was shown an increase of about 38% due to the effect of chemical fertilizer alone. However, the present coffee economical situation in Brasil does not favor the use of fertilizers on o profit basis on the old coffee plantations of the type reported. Considering the advantages of forming new coffee groves according to modern techniques, where there was before pasture lond, a practice which is sure to grow in importance, it would be outdated to recommend expenditures to try to improve old coffee plantations. The irrigation equipmente used for the experiment and part of the laboratory equipment needed was acquired through a donation of the Rockefeller Foundation,, to which we owe due recognition.

This paper describes the statistical analysis of a varietal trial with two unusual characteristics : (i) The plant (coffee) is one of those which show strong maxima and minima of production in alternate years. This phenomenon must be prevented from masking or biasing the other varietal comparisons in which we are interested. (ii) The design of the experiment is systematic. It was laid down in Campinas, Brazil, in 1933 at a time when the principles of randomisation were not so widely known as they are today. THE EXPERIMENT AND DATA. Six varieties are compared, denoted by A B C D E and F (see page 104). They are planted in thirty rows, each with 50 plants, according to the systematic design : A B C D E F A B C D E F A B C D E F A B C D E F A B C D E F Data for twelve years are available in quadro 1 but those of the small and irregular yields in the first two years were discarded. The mean yields of the remaining ten years (1935-1946) appear by figure 1 to be fairly regular and consistent in their behaviour. Most of the plants, but by no means all, showed their maxima in the even years. STATISTICAL ANALYSIS. The quantity of primary interest is the mean yield over the whole period. It is essential that these means should be based (as here) on an even number of years in order to eliminate, from their comparisons, the effect of the alternations of maxima and minima. The magnitude of the oscillation is conveniently measured by total of even years minus total of odd years. Finally we need a linear function of the annual yields for measuring secular trend in order to discriminate varieties which are slowly gaining on the others. The usual linear orthogonal polynomial (with coefficients -9, -7, -5, etc.) is unsuitable because it is not independent of the component of oscillation. A suitable function is obtained instead by using the coefficients -2 -2 -1 -1 0 0 +1 +1 +2 +2. The coefficients of the three linear functions thus defined are set out in quadro 2 (page 107), where it will be verified that they are mutually orthogonal. The effect of the heterogeneity of the soil is as far as possible eliminated (separately for the three functions) by an analysis of covariance, using the number of the row (1-30) as the concommitant observation. A simple linear regression formula is however inadequate. The regressions were taken to the fifth degree by means of orthogonal polynomials. Since the "between varieties" contribution must be removed from the sums of squares and products, the regression coefficients are no longer independently obtainable. It is found however that the normal equations fall into two sets, one yielding the regression coefficients of odd degree and the other those of even degree. Consequently the use of orthogonal polinomiais still effects a considerable saving of work. The computations are set out in full in quadro 3 and in abbreviated form in quadro 4 and 5 for the total, the oscillation and the trend respectively. (Note that the comma indicates the decimal point.) We find that a quadratic regression is adequate for the first and cubic regressions for the others. For the sake of uniformity, a cubic regression was used in every case. The residuals found by subtracting the varietal means from the rows are plotted in figures 2a, 3 and 4a. respectively, together with the regression curves and the 2.5% control limits. These control charts suggest that it is not unreasonable to suppose that the remaining variation is random. Next we use the regression formulae to correct the varietal means. The approximate 80% fiducial intervals of the mean annual yields (kg per row) and the rate of increase of yield (kg per row per year per year) are shown in figures 2b and 4b respectively. In the case of the component of oscillation, the analysis of covariance failed to show the slightest suggestion of differences between varieties. DISCUSSION. An examination of the regressions on number of row reveals the interesting fact that the more fertile portions of the field produce lower yields in the odd years than the less fertile portions. The reason is presumably that the heavier yields in the even years, by exhausting the plant, depress the yields in the following years. The major differences between varietal means over the ten years were sufficiently clear even before the analysis though some of the adjustments are appreciable. A striking fact is that, although there are big general differences between varieties, there are no significant differences between them in respect of the amplitude of oscillation. In other words, the increment of yield in the better varieties is obtained equally in odd and even years. In spite of the large component of oscillation, it is possible to discriminate varieties in respect of their rate of increase of yield (figure 4b). CONCLUSIONS. (i) The extra difficulty introduced by the strong alternations of yield from year to year can be solved b y the choice of suitable orthogonal functions of yearly yields. (ii) Once again a systematic design is found wanting - it fails to eliminate the effect of soil heterogeneity from varietal comparisons. This defect can however be removed, for practical purposes, by an adequate analysis of covariance on row number.

Neste artigo os autores relatam os resultados de mais quatro ensaios de adubação do milho, realizados entre 1949-50 e 1956-57 em diferentes localidades do Estado de São Paulo, e nos quais superfosfato foi comparado com alguns fosfatos naturais, baseando-se o confronto nos seus teores totais de P2O5. Enquanto um dos ensaios foi anual, dois outros foram conduzidos por dois anos e, o quarto, por cinco anos. Em dois dêles também foi estudada a influência da adição de calcário. Tanto o calcário como os adubos só foram aplicados no primeiro ano. Em três ensaios super fosfato foi mui (o superior a Hiperfosfato e, sobretudo, a fosfato Serrote; no outro, os dois últimos fosfatos se mostraram equivalentes e foram apenas um pouco inferiores a super fosfato. Fosfato da Flórida, que só figurou em dois ensaios, comportou-se, em média, como Hiperfosfato. A superioridade de superfosfato proveio principalmente da sua maior eficiência no primeiro ano, pois a partir do segundo os efeitos residuais dos adubos estudados tenderam a se tornar iguais. No ensaio que durou cinco anos a resposta ao calcário foi pràticamente, nula nos dos primeiros anos, mas tornou-se apreciável nos seguintes. E.m outro, conduzido por dois anos em solo mais ácido, o efeito do corretivo foi sofrível no primeiro ano e muito bom no segundo. O calcário tendeu a beneficiar o efeito de superfosfato, mas influiu de modo contraditório sôbre o comportamento dos fosfatos naturais. In this fourth paper on phosphorus fertilizers for corn the authors report the results obtained in four experiments located on different sites of the State of São Paulo, in which superphosphate was compared with three ground rock phosphates, the comparison being based on their contents of total P2O5. While one experiment was annual, the others were conducted for two, two and five years. The effect of liming was also studied in two of the experiments. Lime and fertilizers were applied only in the first year. In three of the four trials superphosphate was much superior to hyperphosphate and mainly to Serrote-phosphate (from the Serrote hill, near Juquiá. State of São Paulo); in the other trial the last two types of phosphates gave similar results and were only a little inferior to superphosphate. Florida-phosphate, included in two experiments, was practically equal to byperphosphate. The superiority of superphosphate came chiefly from its greater efficiency in the first year; star-ling from the second year the tendency was for equivalence of the phosphates studied. In the experiment conducted for five years the lime application was ineffective in the first two years, but il increased appreciably the yields in the following years. In another experiment, couduceted for two years in a move acid soil, lime was fairly effective even in the first and very effective in the second year. The addition of lime enhanced the effect of superphosphate, but affected contradictorily those of the natural phosphates.

Continuando a estudar a eficiência de vários fosfates para a adubação do milho, os autores relatam quatro ensaios realizados em diferentes localidades do Estado de São Paulo. Todos êles foram instalados em 1957-58, mas enquanto dois foram anuais, os outros dois foram conduzidos, sem nova adubação, por mais um e dois anos. Em relação a superfosfato, fosfato bicálcio precipitado, estudado em três ensaios, mostrou-se um pouco mais eficiente em dois e igual em um; Hiperfosíato. que também figurou em três ensaios, foi inferior em um, igual em outro e superior no terceiro; fosfato natural de Olinda, que entrou em quatro ensaios, foi inferior em três e superior em um. No ensaio conduzido por três anos, Hiperfosfato e fosfato de Olinda mostraram-se muito inferiores a superfosfato e fosfato bicálcio nos dois primeiros anos, mas tenderam a igualá-los no terceiro ano; no conduzido por dois anos, superfosfato foi sempre muito superior a fosfato de Clinda. Em um dos ensaios anuais, instalado em solo arenoso aparentemente bem provido de fósforo, o período que se seguiu à semeação correu muito sêco, reduzindo os «stands», sobretudo os dos canteiros que receberam superfosfato; neste ensaio é que êsse adubo se mostrou inferior a Hiperfosfato e fosfato de Olinda. In this paper on phosphorus fertilizers for corn the authors report the results obtained in four experiments located on different soil types of the State of São Paulo. The trials were laid out in 1957-58, but while two of them were annual, the others were conducted for two or three years, the fertilizers being applied only in the first year. In comparison with superphosphate, dicalcium (precipitated) phosphate, which was tested in three localities, was a little more effective in two and equal in one; Hyperphosphate, studied also in three trials, was inferior in one, equal in another and superior in the third; Olinda-phosphate (ground phosphorite from the State of Pernambuco), which figured in the four trials, was inferior in three and superior in one. In the experiment conducted for three years Hyperphosphate and Olinda-phosphate were much inferior to superphosphate and dicalcium phosphate during the first two years, but proved about as effective in the third year; in the two-year experiment, superphosphate was much superior to Olinda-phosphate in both years. In one of the annual experiments, located on sandy soil apparently well provided with available phosphorus, the period that followed sowing was dry and the stands, especially those of the plots with superphosphate, suffered considerable reductions; it was in that experiment that superphosphate was inferior to Hyperphosphate and Olinda-phosphate.

No presente trabalho são relatados os resultados de sete anos de um estudo feito sob a forma de ensino de campo com a finalidade de verificar a possibilidade prática de restauração de lavoura velha de café, no Estado de São Paulo, com o emprêgo da irrigação associada a outras práticas agrícolas. Foram estudados os efeitos da irrigação, inicialmente em diferentes dosagens e os efeitos das combinações fatoriais de NPK (duas dosagens), presença e ausência de estêrco de curral, e presença e ausência de adubação verde intercalar, utilizando o delineamento de blocos ao acaso com canteiros subdivididos, num total de 8 blocos, cada um com 8 tratamentos de 16 plantas, totalizando 2.856 árvores, inclusive as borcladuras, abrangendo a área total de 35.000 m². Foi instalado num dos melhores talhões de cafèzal velho da variedade Bourbon Vermelho, plantado há mais de 40 anos, em terra do tipo rôxa-legítima, desbravada de mato virgem, na atual Estação Experimental de Ribeirão Prêto, do Instituto Agronômico do Estado de São Paulo. A produção media do talhão, em 17 anos, de 1937 a 1953 foi de 31,1 arrobas de café beneficiado por mil pés ou cêrca de 572 kg/hectare e nos últimos 6 anos que precederam à instalação do ensaio alcançou 26,1 arrobas ou 480 kg/hectare. O estudo seqüencial das produções médias quadrienais progressivas revela que a produção do talhão estava em decadência. This paper report and discuss results referring to a field trial set up to study irrigation and fertilization problems of old coffee plantations. The seven year study, started 1953, was conducted at a representative well kept coffee grove of Bourbon variety, about 40 years old, located in a typical purple soil formation of the Ribeirão Preto Experiment Station, considered to be representative of all the region. Eight randomized blocks were used with a 2x2x2 factorial for the small treatments in each block, the following treatments being compared: complete chemical fertilizer in two dosages, with and without organic manure, with and without green manure as annual intercrop. The irrigation treatments included in the first two years application of 1 and 2 inches of water, every 3 weeks, starting July, 2 inches starting August and no irrigation. The remaining 5 years the treatments compared were simply with irrigation and no irrigation. Irrigation application time was determined by soil moisture depletion, when about 55 milimeters were consumed from the 0-80 em soil layer. The results have shown substantial increase in production during dry years, however its significance is diminished by the biennial bearing effect occurring in coffee plants. During wet years irrigation may even diminish production, when heavy rains soon follow the application of water. Use of green manure as annual intercrop was shown not to increase production, the same occurring with the use of organic manure in the dosage of about 12 kg every year per coffee tree (which means a group of 3-5 trees originally planted in the same hole). When production of the treated plots were compared with the untreated border plot trees, it was shown an increase of about 24% due to the effect of chemical fertilizer alone. However, the present economical situation in Brasil does not favor the use of fertilizers on a profit basis. Considering the success obtained in forming new coffee plantation in places where there was before old coffee plantation, a practice which is growing in importance, it would be out dated to recommend expenditures do try to improve old coffee plantation of the type reported. The irrigation equipment used for the experiment and part of the laboratory equipment needed was acquired through a donation of the Rockefeller Foundation, which has cooperated with us whenever needed and to which we owe due recognition.

São relatados os resultados de três ensaios de adubação de arroz de sequeiro, com o cultivar 'Dourado Precoce'. O esquema estatístico foi o fatorial 3 X 3 X 3 para N, P e K, com um tratamento extra de micronutrientes. Os ensaios foram localizados na variação Lins, dos solos Podzolizados de Lins e Marília. Em duas localidades houve efeito para a adubação nitrogenada. A dose de 30 kg/ha de N foi suficiente para o máximo efeito. A adubação fosfatada proporcionou a maior produção com 60 kg/ha de P2O5, em dois casos. No terceiro, esta foi alcançada com 120 kg/ha. O potássio e a mistura de micro-elementos não trouxeram acréscimos significativos na produção. This paper deals with three fertilizer experiments with upland rice, in which the cultivar 'Dourado Precoce' was used. The scheme used was a factorial 3 X 3 X 3 with an extra treatment for micronutrients and the experiments were installed on Podzolized soils on Calcareous Sandstone Lins variation. In the choice of the places, special consideration was given to the e.mg PO4-3 /100g of soil content. Nitrogen affected the production in two places. 30 kg/ha of N was sufficient. Phosphorus affected the production in the three places. The level of 60 kg/ha of P2O5 was sufficient in two places and in the third, the level of 120 kg/ha of P2O5 was necessary. Potassium and micronutrients did not affect the production of rice.

This paper presents the results of three N, P, K, S mineral fertilizer trials on wheat (Triticum aestivum L.), carried out in 1969, 1970 and 1971 at Monte Alegre do Sul, SP, on a massape type of soil. The responses observed in these trials present a highly significant effect to nitrogen, a little effect to phosphorus, and significant effect to potash. Every 30 kg N/ha increased 215 kg/ha the production. The effect of sulphur increased 10% the production in relation to the check treatment and 11% in relation to the complete mineral fertilizer. The quantities of N-P-K fertilizer to be applied for massape type of soil were calculated for several relationships between wheat and fertilizers prices.

Neste artigo são apresentados os resultados de seis experiências preliminares de adubação da mamoneira, realizadas entre 1941-42 e 1950-51 em quatro tipos de solo do Estado de São Paulo, e nas quais se procurou determinar o efeito do azôto, do fósforo e do potássio sôbre a produção de sementes. As doses usadas variaram, conforme a experiência, entre 20 e 30 kg/ha de N, 35 e 50 kg/ha de P2O5, e 25 e 30 kg/ha de K2O. A resposta ao azôto foi satisfatória em três experiências, mas somente em uma alcançou significância estatística. O fósforo também obteve três respostas satisfatórias, mas não significativas. O efeito do potássio foi negativo ou praticamente nulo nas seis experiências. Em algumas experiências os adubos não produziram efeito favorável porque os solos utilizados aparentemente deles não precisavam. Outros casos de efeitos muito pequenos ou negativos são, em grande parte, atribuídos à aplicação dos adubos conforme o método tradicional em nosso meio, nos sulcos de plantio, ao ser este efetuado. Parece que para esses resultados também contribuíram o plantio demasiado tarde, em duas experiências, e, em todas elas, o uso de espaçamentos muito mais largos que os presentemente julgados ótimos. Exame detalhado indicou que a eliminação dêsses inconvenientes concorrerá para aumentar a freqüência de resultados satisfatórios. This paper reports the results obtained in six preliminary experiments conducted between 1941-42 and 1950-51 in the State of São Paulo, to study the effect of moderate rates of nitrogen, phosphorus and potassium on the yield of castor beans. The response to nitrogen was satisfactory in three tests, but only in one it was statistically significant. Phosphorus also promoted satisfactory responses, in three experiments, but they did not reach the level of significance. The effect of potassium was negative or very poor in all the trials. Some of the experiments were located on soils apparently well provided with one or more of the nutrients tested. Other cases of poor results are partly attributed to the application of the fertilizers in the traditional method, which consists in adding them (inclusive the whole dose of nitrogen) to the furrows just before planting and mixing them slightly with the soil. Contributed also for the poor results obtained: a) two of the experiments were planted too late, and b) the plant density used in all of them was much lower than the optimum as learned in later investigations.

No presente trabalho são relatados os resultados das experiências que constituem a décima segunda e décima terceira séries de ensaios de variedades de amendoim instaladas em Campinas, Ribeirão Prêto e Presidente Prudente, em 1955/56 e 1956/57. Das 10 variedades que entraram era competição, a Paulista-269 é a que se tem destacado, tanto pela produção de vagens como pelo teor em óleo, não obstante outras também terem se mostrado promissoras, tais como Bandeirante-263, Centenário-264, Brasília-265 e Virgínia-266. A variedade Tatuí-76 também se tem revelado bem produtiva e com bom rendimento em óleo, enquanto a Tatu-53, a mais difundida entre nossos lavradores, tem sido uma das piores em competição. In this paper the results of two series of variety trials with peanut are reported. The experiments were conducted at the counties of Campinas, Ribeirão Preto and Presidente Prudente, in the State of São Paulo, during the years 1955/56 and 1956/57. One of the ten varieties in competition, namely Paulista-269 distinguished both for its pod production and oil content; are promising also the varieties Bandeirante-263, Centenário-264, Brasília-265 and Virgínia-266. The Tatuí-76 variety is a good yielder, with good oil content, while the variety Tatu-53, the most grown all over the State, is one of the lowest yielders.

This paper continues the statistical analysis of a coffee varietal trial at Campinas (1, 2, 3), utilising the data of a further period of 4 years. Variety D (Yellow Bourbon) has now drawn significantly ahead of C (Bourbon) as is shown by fig. 1 compared with fig. 2b of reference (3). This possibility was foreseen at the time of the earlier analysis (3), from a consideration of the annual rates of increase of yield. This is of interest to the general problem of selection of perennial plants, because it shows that not only average yield but also rate of increase of yield is a useful criterion for selection.