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The objective of this study was to evaluate the canopy insect community associated with maize intercropped with different arrangements of Crotalaria spectabilis and the effects on the damage caused to maize by Spodoptera frugiperda and Helicoverpa zea. The treatments were intercropping systems of maize with Crotalaria spectabilis: CR - Crotalaria spectabilis sown on the same rows as maize; CBR - Crotalaria spectabilis sown between the rows of maize; CRBR - Crotalaria spectabilis sown on the rows and between the rows of maize, and M - maize monocrop. The experimental plot consisted of five rows of maize, five meters long, spaced 0.8 m apart. Assessments were made of the following parameters: insect community present in the maize canopy, leaf damage caused by the fall armyworm (S. frugiperda) and the corn earworm (H. zea), maize grain yield and shoot dry weight of maize and crotalaria. The CRBR intercropping system was characterized by the presence of predators and parasitoids, especially from the families Forficulidae and Braconidae: 79% and 82%, respectively. The maize monocrop, in turn, was mainly characterized by the presence of chewing and sucking phytophagous insects and predators. There was no influence of plant arrangements on the damage to maize caused by S. frugiperda (mean variation between 0.47 and 0.64 of damage) and H. zea (ranging between 6.42 and 7.49 of damage), neither on the grain yield of the crop (variation between 4129.57 kg ha-1 and 5653.77 kg ha-1). Our results suggest that C. spectablis sown in the rows and between the rows of maize has the potential to optimize conservative biological control, without, however, affecting the grain yield of the cereal

Common sorrel is a non-conventional vegetable of the family Polygonaceae, naturalized in Brazil and still with few nutritional and sensory studies. The aim of this work was to evaluate the physicochemical and sensory characteristics of Common sorrel, harvested at 60 days. Common sorrel was evaluated regarding the ascorbic acid content, total phenolic compounds, instrumental color: Luminosity (L*), chroma, Hue and chlorophyll. To describe the profile of the sensory attributes, 14 evaluators were used, and 52 for the acceptance test and purchase intention. Common sorrel presented 10.25 mg/100 g-1 of ascorbic acid, 290.51 mg / 100 g-1 of total phenolics and in the instrumental analysis of color, it presented L*, chroma and Hue of 49.28, 25.24 and 122.5, respectively. For chlorophyll index, 36.60 SPAD was observed. The sensory attributes described for Common sorrel using structured scale of 9 cm were: green coloration (4.6) and irregular leaf shape (4.3), aroma of grape skin (5.1), sour and bitter tastes (5.1 and 5.4 respectively), smooth texture (5.7), very thin leaf (3.3), soft texture (5.5) and flexible leaf (6.9). It was verified that Common sorrel obtained scores between 6 (liked very much) and 7 (loved it) for the acceptance of color, flavor, texture and global acceptance of the leaf. Regarding aroma, 32.7% of the scores were inferior to 4. Regarding purchase intention, 65.4% of the evaluators answered that they would certainly buy this vegetable. Although little known, this vegetable was well-accepted by the evaluators, demonstrating the potential for consumption. Key words: Acceptance; Color; Phenolic compounds; PANC.

One of the biggest obstacles to organic maize cultivation is weed management. The aim of this work was to evaluate the mowing and weeding in the control of densities of Ipomoea triloba (morning glory) in competition with maize. The experiment was installed in a completely randomized design, with four replications, in the factorial scheme 3 x 3 + 1. The first factor was constituted by three densities of the species I. triloba and the second by three weed management. The additional treatment consisted in the cultivation of maize free from I. triloba interference. The mowing done in the V4 stage of maize did not minimize the competition of I. triloba. Weeding was more efficient for control at higher densities. The I. tribola showed regrowth and despite accumulating reduced dry mass, it was more efficient in the uptake of N, P, K, and Mg in relation to the uncropped plants.

One of the main difficulties in the organic, no-tillage system is weed management. The aim of this study was to evaluate the effect of the association between mechanical and cultural control methods (reduction of spacing and consortium with Canavalia ensiformis DC) on weed phytosociology and grain yield in maize with the organic, no-tillage system. The experiment design was a randomized complete block design with four replications, in a 2x3x2 factorial scheme, where the factors were, first factor: presence and absence of C. ensiformis; second factor: three weed management methods (without control, mowing and weeding), and third factor: two maize spacings (0.4 and 0.8 m). We evaluated the phytosociology of the weed community in maize stages V4 and V8, maize yield and dry matter of C. ensiformis. In the V4 stage, 21 weed species were identified, which were reduced to 16 species in V8. Cyperus rotundus presented a higher IR (Importance Value Index) in V4, and Panicum maximum had the highest IR in V8, independent of management. The C. ensiformis consortium with maize with 0.8 m spacing and weeding provided a higher grain yield. RESUMEN Una de las principales dificultades en el sistema orgánico de siembra directa es el manejo de malezas. El objetivo de este estudio fue evaluar el efecto de la asociación de métodos mecánicos y de control de cultivos (reducción de espaciamiento y cultivos intercalados con Canavalia ensiformis DC) en la fitosociología de malezas y el rendimiento de granos de maíz bajo un sistema de siembra directa orgánico. El diseño experimental fue de bloques al azar con cuatro repeticiones, en un esquema factorial 2x3x2, con el primer factor: presencia y ausencia de C. ensiformis; segundo factor: tres métodos de manejo de malezas (no controlado, corte y deshierbe), tercer factor: espacio entre dos hileras (0,4 y 0,8 m). Se evaluó la fitosociología de la comunidad de malezas en las etapas V4 y V8 del maíz, el rendimiento de grano del maíz y la materia seca del C. ensiformis. En la etapa V4 se identificaron 21 especies de malezas, reduciéndose a 16 especies en V8. Cyperus rotundus tiene la mayor IR (importancia relativa) en V4 y Panicum maximum la mayor IR en V8, independientemente del manejo. C. ensiformis en consorcio con maíz en el espacio de 0,8 m con desmalezado proporcionan un mayor rendimiento de grano.

A reduzida oferta de sementes de milho orgânicas no mercado, somado a escassez de informacoes sobre a producao e qualidade das mesmas estao entre os principais entraves para a producao de milho orgânico no Brasil. O presente trabalho objetivou avaliar o potencial fisiologico das sementes de cultivares comerciais e crioulas de milho produzidas em sistema orgânico na colheita e apos o armazenamento. O experimento foi conduzido no Centro de Ciencias Agrarias, da Universidade Federal de Sao Carlos no campus da cidade de Araras, SP, no Laboratorio de Producao Vegetal e Recursos Florestais de maio a outubro de 2016. Foram utilizadas sementes de sete cultivares de milho: variedades comerciais Al Avare, Al Bandeirantes e Al Piratininga, variedades crioulas Santa Rita 1 e Santa Rita 2 e, dois hibridos simples 30F53 e 2B587, produzidas em sistema orgânico na safra 2015/2016. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 7 x 2 com quatro repeticoes. Primeiro fator foram as sementes dos cultivares de milho e o segundo o tempo de armazenamento em garrafas PET (pos colheita e 90 dias). Foram avaliados: massa de 1000 sementes, grau de umidade, teste de germinacao, primeira contagem, germinacao apos envelhecimento acelerado e indice de velocidade de emergencia (IVE) em leito de areia. Os resultados foram submetidos a analise de variância e as medias foram comparadas pelo teste de Tukey a 5% de significância. As sementes apresentaram elevado vigor e porcentagem de germinacao, mantendo a qualidade mesmo apos 90 dias de armazenamento em garrafa PET.

A espécie e densidade de adubos verdes no consórcio com o milho modificam os padrões de competição interespecífica podendo alterar as respostas de temperatura e umidade do solo. Objetivou-se, neste estudo, analisar os efeitos da Crotalaria spectabilis e do Cajanus cajan na temperatura e umidade do solo, ao longo dos estádios de desenvolvimento do milho cultivado em consórcio, em sistema orgânico. O delineamento experimental foi blocos casualizados, com quatro repetições. Os tratamentos consistiram em três consórcios de milho: MC - Crotalaria spectabilis (5 plantas m -1); MG - Cajanus cajan (5 plantas m -1); MCG - Crotalaria spectabilis e Cajanus cajan (10 plantas m -1, cinco plantas de cada adubo verde), semeados na linha do milho e três tratamentos controles: M - milho; C - Crotalaria spectabilis e G - Cajanus cajan, solteiros. As leituras das temperaturas do solo foram realizadas na linha e entrelinha de semeadura, e, da umidade do solo, na linha de semeadura do milho, nos horários de 8, 12 e 17 horas, nos estádios fenológicos V5, V8, VT, R2, R4 e R6 do milho. As profundidades de avaliação foram 0-0,10, 0,10-0,20 e 0,20-0,40 m. Os horários, as profundidades e as posições linha-entrelinha influenciaram a temperatura do solo, enquanto as profundidades e os estádios fenológicos influenciaram a capacidade de retenção de umidade no solo. Os consórcios reduziram a temperatura do solo, principalmente o MG, que também reduziu a umidade do solo entre os estádios V8 e R2 do milho.

A redução no número de variedades comerciais disponíveis, a partir da liberação de cultivares transgênicas de milho, compromete a autonomia e a consolidação de sistemas orgânicos de produção. Objetivou-se avaliar, em duas localidades com altitudes distintas, características agronômicas e componentes de produção de cinco variedades comerciais (AL Avaré, AL Bandeirante, Cativerde 02, AL Piratininga e UFVM 200 - Soberano) e duas variedades crioulas (Santa Rita 1 e Santa Rita 2), em sistema orgânico de produção. O experimento foi conduzido em esquema fatorial 2x7, sendo o primeiro fator dois locais com altitudes distintas (Muzambinho/MG, 1100 m de altitude e Araras/SP, 665 m de altitude) e o segundo fator composto por sete variedades de milho, em delineamento de blocos casualizados, com quatro repetições. Avaliou-se diâmetro de colmo, altura de plantas, altura de inserção e número de folhas acima da espiga superior, índice de clorofila total Falker, teor de nitrogênio foliar, número de fileiras por espiga, de grãos por fileira e de grãos por espiga, acamamento, estande final, peso de 1000 grãos e produtividade. O ambiente, principalmente os efeitos da altitude, temperatura média noturna e diurna e a distribuição da precipitação pluviométrica, mostrou-se o fator mais importante para o rendimento de grãos de milho. O comportamento agronômico de todas as variedades foi superior em Muzambinho. A variedade AL Piratininga apresentou adequado desempenho agronômico tanto em alta quanto em baixa altitude e, em ambos os locais, as variedades crioulas apresentaram desempenho semelhante ao das convencionais.

Intercropping is a technique which consists of cultivating two or more species in the same area. In these systems, planning and management should be carried out in order to avoid interspecies competition for water, light, and nutrients. This paper aimed to evaluate macronutrient content and accumulations in corn (Zea mays L.) intercropped with dwarf pigeon pea (Cajanus cajan L.) in different plant arrangements. The experimental design adopted was one of randomized blocks, with six treatments and four repetitions. The treatments consisted of different arrangements of dwarf pigeon pea intercropped with corn: corn in monoculture, dwarf pigeon pea sown in the same rows as the corn, one row of dwarf pigeon pea sown between the rows of corn, dwarf pigeon pea sown in the same rows and in a row between the corn, and dwarf pigeon pea sown in the same rows and in two rows between the corn. The following variables were evaluated: dry matter (t ha-1), macronutrient content and accumulations (g kg-1), total chlorophyll in the corn leaves (FCI) and grain yield of corn, as well as dry matter production (t ha-1) and macronutrient content in the aerial part of the dwarf pigeon pea (g kg-1). The arrangement with dwarf pigeon pea sown in the same rows and in two rows between the corn increased N content in the corn plants, in relation to the other arrangements and the corn in monoculture. Ca content and accumulations were higher in corn in monoculture and in the arrangement with dwarf pigeon peas sown in the same rows as the corn. Key words: Zea mays L., Cajanus cajan, interspecies competition, plant nutrition.

The citrus yield in Brazil is not ranked among the best in the world, potentially due to inadequate management by citrus growers. The low adoption of conservation agriculture (CA) techniques and the improper application of herbicides are also well-known problems. Thus, this study evaluated the use of CA techniques, and twoUrochloaspecies (ruzi grass and signal grass) were used as cover crops. Two different types of mowers (ecological, EM; conventional, CM) launched the mowed biomass into different positions within a young Tahiti acid lime orchard (up to four years old). In addition, the integration of glyphosate into this management system was evaluated, with (GLY) and without (NO GLY) glyphosate application. This experiment was conducted across three growing seasons (2011-2014), in Mogi Mirim, São Paulo State, Brazil. The cover crop biomass yields and the effects of the mowing treatments, weed density, vegetative growth and fruit yields of the Tahiti acid lime trees were evaluated. In terms of major results, signal grass produced higher biomass yield values (up to 64%) than ruzi grass; EM promoted higher mowed biomass values in the intra-row (up to 5.1 ton ha−1, 9.0 times higher than CM), and a higher canopy volume (up to 33% than CM). These results were enhanced when ruzi grass was associated with the EM (56% lower weed density; 126% higher fruit yield than CM) and with GLY (52% higher fruit yield than NO GLY); and EM with GLY (43% lesser weed density and 107% higher fruit yield than NO GLY). Overall, ruzi grass was a good cover crop because it provided less competition for the citrus trees, EM provided a mulch layer in the intra-row of the citrus trees, and associated with GLY, these approaches could provide options for an integrated and more sustainable weed management, primarily for young Tahiti acid lime orchards.

Objetivou-se com este trabalho avaliar as alteracoes nos atributos quimicos de um Latossolo Vermelho, com pH e teores de nutrientes adequados, cultivado com feijoeiro (Phaseolusvulgaris L.), em sucessao a plantas de cobertura e a aplicacao de vinhaca e deremineralizador (po de basalto). O ensaio foi realizado em casa de vegetacao, no delineamento experimental de blocos casualizados em esquema fatorial 4x4x2, com tres repeticoes. O primeiro fator foram doses de remineralizador (0, 2, 4 e 8 t ha-1 depo de basalto). Pousio (controle) e as plantas de cobertura crotalaria (CrotalariajunceaL.), milheto (Pennisetumglaucum(L.) R. Brown) e braquiaria (Urochloa cv. ruziziensisGermain &Evrard) representaram o segundo fator. O terceiro fator foi a aplicacao ou nao de vinhaca (200 m3 ha-1 e 0 m3 ha-1, respectivamente). Os atributos quimicos analisados, aos 110 dias apos incubacao do remineralizador, foram: materia orgânica do solo (MOS), pH em CaCl2, acidez potencial (H+Al), soma de bases (SB), capacidade de troca de cations (CTC) e saturacao por bases (V).Tratamentos com vinhaca e remineralizador, associadas amilheto e crotalaria, proporcionaram aumento do pH e de V e diminuicao de H+Al. Conclui-se que feijoeiro cultivado em sucessao a plantas de cobertura cultivadas com po de basalto e vinhaca pode viabilizar a transicao de um sistema de manejo convencional da adubacao de solo para um manejo com insumos alternativos.

A fauna edáfica tem sido amplamente utilizada como bioindicadora da qualidade do solo em agroecossistemas por responder rapidamente às alterações decorrentes do uso e manejo em sistemas agrícolas. Objetivou-se neste estudo avaliar a fauna do solo associado a sistemas de cultivo convencionais e sustentáveis. Os sistemas estudados foram cana convencional, cana orgânica, milho orgânico consorciado com guandu-anão, milho orgânico em monocultivo, sistema agroflorestal, solo em pousio e vegetação nativa. Foram instaladas, em cada área, quatro armadilhas de queda (“pitfall”) para captura dos organismos da fauna do solo, ao longo de um transecto, equidistantes de 5 m, totalizando 28 armadilhas. Coletou-se um total de 1330 indivíduos, distribuídos em 50 táxons, sendo Formicidae, Collembola e Diptera: Phoridae os predominantes. Os indivíduos pertencentes ao grupo trófico funcional predadores foram os mais representativos na maioria das áreas estudadas. Os sistemas pousio, agrofloresta, cana convencional e vegetação nativa mostraram maior abundância de indivíduos da fauna do solo. A riqueza de grupos foi maior nos sistemas com milho orgânico em monocultivo, consorciado com guandu-anão e pousio, com as duas áreas de milho apresentando maior uniformidade na distribuição dos grupos da fauna do solo. Estes resultados podem auxiliar na classificação de alguns grupos de invertebrados como bioindicadores de qualidade do solo em agroecossistemas.

The use of shade trees in coffee fields have been motivated by climatic changes. However, microclimatic conditions in shaded coffee fields differ due to shade tree spatial distribution and species, altering physiological responses of coffee trees. This study aimed to evaluate the effects of shade tree spatial distribution and species on coffee trees photosynthetic rate in two growth seasons, of high (HSD) and low (LSD) sink demand. The experimental design consisted of randomized blocks with three replicates in split-split-plots. Plots were the shade tree species: Anadenanthera falcata, Cassia grandis and Peltophorum dubium. Split plot was formed by five distances between coffee trees and shade tree trunks: coffee trees on planting row of shade trees, distancing one (D1L) and five (D5L) meters from shade trees trunk; coffee trees on inter-rows of shade trees, parallel to D1L and D5L (D1E and D5E); coffee trees distancing 77 meters from shade tree trunks, in a full-sun field (PS). The split-split-plots correspond to coffee tree canopy exposure to the sun: branches facing North or South. Shade trees canopy density and occupation was evaluated with a convex densiometer. Photosynthetic rate (Pn)and photosynthetic active radiation (PAR) were measured with an Infrared Gas Analyzer (IRGA) on two time-frames, between 7.00 and 9.00 solar hours and between 11.00 and 13.00. Shade tree canopy density and occupation was not homogenous during the change of seasons and shift due to spatial distribution, which also changes PAR levels. Shade trees reduce PAR to more suitable values for coffee tree exploitation, especially on D1L and D5L. During HSD, shading did not affect Pn, which was greater in branches facing North. Yet, in LSD, between 11.00 and 13.00, coffee trees shaded with A. falcata showed greater Pn than at PS. Coffee trees shaded with C. grandis at D5L and D1E had greater values of Pn than PS.

Sorrel (Rumex acetosa L.) is an unconventional food plant. It is a perennial herbaceous plant that forms thickets. There are studies related to the accumulation of nutrients in sorrel, but there is no information on its absorption march and vegetative development. The objective of this study is to determine macronutrient absorption and biometric parameters of sorrel during 60 days after seedling transplantation (DAT) of seedlings. The experiment was completely randomized with eight treatments and four replications. It was conducted in a greenhouse. The treatments consisted of plant collection times, performed at 15, 20, 25, 30, 35, 40, 50 and 60 DAT. Plants’ biometric parameters (leaf blade length, relative leaf area, and shoot fresh and dry matter) and macronutrient absorption march were evaluated. Biomass, leaf blade length and relative leaf area of sorrel plants increased over time and, more markedly, after 35 DAT. The maximum levels of macronutrients accumulated in sorrel shoots, in descending order, were K > N > Ca > Mg > P > S. There was no significant difference in Ca and S contents among collection times, that is, the absorption and accumulation of these nutrients by sorrel did not vary throughout the evaluation time.

Avaliou-se a eficiência do uso de roçadas no controle de picão-preto (Bidens pilosa) e trapoeraba (Commelina benghalensis) por meio de características morfológicas e fisiológicas do milho. O experimento foi realizado em condições controladas no ano agrícola 2009/2010. As características fisiológicas foram obtidas em parcela subdividida, sendo realizadas quatro avaliações no decorrer do ciclo do milho: 1ª - antes da primeira roçada (V3); 2ª - após a primeira roçada (V6); 3ª - após a segunda roçada (V9); e 4ª - plantas de milho no estádio de florescimento, por meio de um analisador de gases no infravermelho. Duas roçadas reduziram a interferência das plantas daninhas B. pilosa e C. benghalensisnas características morfológicas do milho. A roçada não influenciou os aspectos fisiológicos nas plantas de milho em competição com as plantas daninhas. C. benghalensis causou maior interferência nas características fisiológicas do milho, reduzindo a fotossíntese e a transpiração. A espécie B. pilosa, quando não roçada, apresentou maior capacidade de interferência na morfologia do milho. The efficiency of using clearings to control Picão-preto (Bidens pilosa) and Trapoeraba (Commelina benghalensis) was evaluated based on the morphological and physiological characteristics of corn. An experiment under greenhouse conditions was conducted in 2009/2010. The physiological characteristics were obtained in a subdivided parcel, with four evaluations being performed throughout the corn cycle (1- before the first clearing (V3); 2- after the first clearing (V6);3- after the second clearing (V9); and 4- corn plants at the fluorescence stage), by means of Infra Red Gas Analyzer. Two clearings reduced the influence of B. pilosa and C. benghalensis weeds on the morphological characteristics of corn. The clearing did not influence the physiological aspects of the corn plants in competition with weeds. C. benghalensis caused a greater interference in the physiological characteristics of corn, reducing photosynthesis and transpiration. When not cleared, B. pilosa species had a greater capacity of interfering in corn morphology.

The objective of this study was to evaluate the biometric parameters and leaf nutrient content of common bean ( Phaseolus vulgaris L.) grown in succession to cover crops, as a function of the application of remineralizer doses (basalt powder) and vinasse. The experiment was conducted in a greenhouse in the experimental design of ran­domized blocks in a 4x4x2 factorial scheme, with three replications. The first factor was remineralizer doses (0, 2, 4, and 8 t ha -1 basalt powder). The treatments with no cover crops (control) and with the cover crops crotalaria ( Crotalaria juncea L.), millet ( Pennisetum glaucum L.), and brachiaria ( Urochloa cv. ruziziensis ) constituted the second factor. The third factor corresponded to the presence or absence of vinasse (200 m 3 ha -1 , and 0 m 3 ha -1 , respectively). Plant height, shoot dry matter (SDM), leaf area index (LAI), Falker chlorophyll index (FCI), and leaf macronutrient content (N, P, K, Ca, Mg, and S) were evaluated. The association of cover crops, vinasse and remineralizer increased plant height and leaf contents of K, Ca, Mg, and S at the evaluated stage, but vinasse had a positive effect only on S content. Remineralizer doses associated with cover crops provided satisfactory levels of leaf macronutrients for common bean.

O objetivo deste trabalho foi verificar a eficiência de métodos de controle mecânico e diferentes densidades populacionais de picão–preto (Bidens pilosa), capim–braquiária (Brachiaria decumbens) e capim–marmelada (Brachiaria plantaginea) e suas interferências nos componentes de produção do milho, visando o manejo orgânico. O experimento foi instalado em casa de vegetação, no delineamento inteiramente casualizado, com três repetições, no esquema fatorial 3 x 3 + 1. O primeiro fator foi constituído por três densidades de plantas daninhas (duas, quatro e seis plantas por vaso) e, o segundo, pelos manejos: roçada das plantas daninhas nos estádios de quatro e oito folhas do milho; capina das plantas daninhas no estádio de quatro folhas do milho; milho sem controle das plantas daninhas; e o tratamento adicional milho cultivado sem as plantas daninhas (testemunha). O cultivar de milho utilizado foi o UFVM 100, semeado simultaneamente com as plantas daninhas em vasos contendo 18 L de substrato (solo + composto orgânico). Para a espécie Bidens pilosa, a roçada e o tratamento sem controle foram os que mais interferiram na produção de matéria seca (MS) das folhas do milho. Em se tratando das variáveis MS das folhas, dos colmos e dos órgãos reprodutivos do milho, não houve diferenças significativas entre a capina e o tratamento em que o milho foi cultivado sem a planta daninha, indicando que a roçada não proporcionou controle eficiente da espécie Bidens pilosa no cultivo do milho orgânico. Quanto a B. plantaginea, a roçada e a capina proporcionaram o mesmo acúmulo de MS quando o milho conviveu com duas plantas da espécie daninha, porém nas maiores densidades, quatro e seis plantas por vaso, o tratamento com roçada foi semelhante ao sem controle, demonstrando que a roçada é eficiente no controle de B. plantaginea apenas quando esta se encontra em baixa densidade populacional. Para B. decumbens, a densidade de seis plantas por vaso foi a que proporcionou maior redução de MS das folhas do milho, independentemente do manejo. The objective of this work was to verify the efficiency of mechanic control methods and different populational densities of Bidens pilosa, Brachiaria decumbens and Brachiaria plantaginea and their interference in corn production components, for organic management purposes. The experiment was conducted in a green house, in a completely randomized design, with three replicates, in a factorial scheme 3x3+1. The first trial was composed by three weed densities and the second by the treatments (weed cutting at four and eight developed leaf stages, hand–weeding at four developed leaf stage, corn without weed control, and an additional treatment, corn without weed (control). The corn cultivar UFVM 100 was sowed simultaneously with the weeds in 18L pots filled with substrate (soil + organic matter). For Bidens pilosa, the greatest interference in leaf dry matter was observed in the cutting and without weed control treatments. When corn was cultivated without weeds and hand–weeded, no significant differences were observed in leaf dry matter, stem and reproductive organs, indicating that cutting was not efficient at controlling Bidens pilosa under organic corn crop conditions. When corn was planted together with B. plantaginea plants, cutting and hand–weeding provided the same dry matter accumulation; however, at higher densities (four and six plants/vase), the cutting and corn without weed control treatments were similar showing that cutting is efficient in controlling B. plantaginea at a low population density. B. decumbens showed the highest leaf dry matter reduction at a six plant/vase density, regardless of the type of treatment.

The exclusive use of organic compost in the production of organic vegetables has been found to be a costly practice due to the high volume of compost demanded to obtain commercial productions. Thus, one of the alternatives for complementary fertilization of vegetables is the use of green manure. The objective of this work was to evaluate three green manure species, used to complement the fertilization with organic compost, in relation to the nutrient contents in their biomass, and to productivity and agronomic traits of crisphead lettuce and cabbage. The experiment was carried out at the Olericulture Sector of the Federal University of Lavras (UFLA), in Lavras, Minas Gerais State, Brazil, from December 2001 to August 2002, in a soil classified as Udox. The experiment was arranged in a randomized block design in a factorial scheme (4x2) with three repetitions. The first factor was constituted by the green manure species: black-velvet bean (Stizolobium aterrimum), jack bean (Canavalia ensiformis), and sunnhep (Crotalaria juncea), plus a control treatment (weed and mineral fertilizers); and the second factor was constituted by the vegetable crops: crisphead lettuce and cabbage. Among the tested green manure species, sunnhep presented the best potential for extraction of N, P, K, Mg, B, Mn and Zn. In addition, sunnhep was more efficient than jack bean or black velvet bean in increasing the commercial weight of cabbage head. In relation to productivity, as for lettuce, green manuring plus organic compost did not differ from the control; while for the cabbage, these treatments had a performance statistically inferior. The use of green manure plus organic compost allowed to obtain commercial crisphead lettuce and cabbage heads with satisfactory weight for the market.

Objetivou-se com esse trabalho avaliar o efeito da distribuição espacial de árvores (Anadenanthera falcata, Albizia polycephala e Cassia grandis) em cultivo de cafeeiro sombreado (Coffea arabica cv. Obatâ), sobre a resistência mecânica, umidade e propriedades químicas do solo. O delineamento experimental foi o de blocos casualizados com quatro repetições, em esquema fatorial 4x2. O primeiro fator foi a localização dos pontos de amostragem do solo no cafezal sombreado, determinados por dois pontos na mesma linha de plantio das árvores (D1L - um metro de distância do tronco da árvore e D6L - seis metros de distância do tronco da árvore) e dois pontos paralelos a esses localizados na entrelinha de plantio das árvores (D1E e D6E). O segundo fator foi a profundidade de coleta do solo: 0,0-0,20 m e 0,20-0,40 m. As maiores resistências mecânicas do solo à penetração foram observadas nos pontos D1L e D1E, com 8,89 Mpa e 6,55 Mpa, respectivamente. O menor valor de pH (4,62) e o maior teor de alumínio no solo (4,95 mmolc dm-³) foram encontrados na linha de plantio das árvores, no ponto D1L. A distribuição espacial das árvores não alterou a umidade do solo, variando entre 0,11 e 0,14 kg kg-1e os teores de matéria orgânica, fósforo, potássio, cálcio e magnésio, os quais se mantiveram dentro das faixas consideradas adequadas para o cultivo do cafeeiro. Conclui-se que as árvores avaliadas elevam a resistência do solo à penetração e provavelmente exercem maior competição por nutrientes com o cafeeiro, aumentando o pH e os teores de Al do solo, quando localizadas no ponto D1L, possivelmente, em função da distribuição e concentração das raízes das mesmas. Contudo, a distribuição das árvores não influenciou a umidade e os teores de matéria orgânica, P, K e Ca do solo.

The aim of this work was to evaluate the effect of nitrogen application mode and spacing on corn culture. The study was carried out in 2003/04 agricultural years, at the Experimental Station of Coimbra – UFV. The experiment was installed in a complete randomised block design. Treatments were arranged in a 3 x 3 x 2 factorial scheme with four replicates (three cultivates - UFVM 100, AG 9010 and AG 1051; three nitrogen application modes - 0, 120 kg ha -1 of N in planting and 30 kg ha -1 at sowing + 90 kg ha -1 at four fully expanded leaves; and two plant spacing – 1.0 and 0.5 m). Either at sowing or parcel out, the nitrogen application increased the plant height in all plant spacing used; the spacing reduction, from 1.0 m to 0.50 m, provided an increase of 8% in grains productivity; the 120 kg ha -1 nitrogen application, either at sowing or divided in two modes (30 kg ha -1 at sowing and 90 kg ha -1 at four fully expanded leaves), did not show any effect on the characteristics evaluated.

A demanda por minitomates do tipo grape tem-se mostrado em ascensão no mercado brasileiro. A adubação verde em cultivo consorciado com o minitomateiro e a utilização de efluentes tratados provenientes de indústria de laticínios para irrigação são técnicas sustentáveis que podem viabilizar a produção econômica desta cultura. O objetivo do trabalho foi avaliar a produtividade e qualidade do minitomateiro cultivado em sistema de consórcio com adubos verdes fertirrigados com efluente tratado de laticínio. O delineamento foi em blocos casualizados em esquema fatorial (5 x 2) com quatro adubos verdes em consório com o minitomateiro: Canavalia ensiformis (feijão-de-porco), Crotalaria spectabilis (crotalária-espectábilis), Lupinus albus (tremoço-branco) e Pennisetum glaucum (milheto) e uma testemunha (sem adubação verde - minitomateiro solteiro), e duas fontes de água utilizadas na fertirrigação (água de torneira e efluente anaeróbio tratado), com quatro repetições. O efluente tratado por sistema anaeróbio foi caracterizado quinzenalmente ao longo do experimento e foram avaliados: a diagnose foliar do minitomateiro, produção de fitomassa dos adubos verdes e acúmulo de nutrientes, produtividade, composição química e qualidade de frutos do minitomateiro e eficiência de uso da água. Os maiores teores de nitrogênio foram determinados nas folhas do minitomateiro solteiro fertirrigado com água de torneira e para o minitomateiro em consórcio com crotalária-espectábilis fertirrigado com efluente anaeróbio tratado. A aplicação do efluente tratado de laticínio supriu de maneira adequada o fornecimento de nitrogênio ao minitomateiro. Os adubos verdes, com exceção do milheto, não competiram por nutrientes com o minitomateiro, no entanto, não favoreceram a produtividade do minitomateiro. O maior número de fruto ocorreu para o cultivo solteiro e para o minitomateiro em consórcio com tremoço-branco. Os frutos do minitomateiro grape apresentaram maior teor de sólidos solúveis totais quando fertirrigados com efluente tratado de laticínio. Os consórcios com crotalária-espectábilis e feijão-de-porco apresentaram as maiores eficiências de uso da água na produção de frutos, e os tratamentos fertirrigados com água de torneira apresentaram maior EUA em comparação aos fertirrigados com efluente anaeróbio. A utilização do efluente anaeróbio tratado de laticínio reduziu em média 90,89 % da aplicação de nitrogênio via fertilizante. É possível substituir a água pura ou potável pelo efluente tratado de laticínio na fertirrigação do minitomateiro. The consumption of cherry tomato has been on the rise in the Brazilian salad market. The green manures in intercropping with the cherry tomato and the use of treated effluents from the dairy industry for irrigation are sustainable techniques that can allow the economic production of this crop The objective of the present work was to evaluate the productivity and post-harvest of the cherry tomato cultivated in a consortium system with different green manures, fertirrigated with treated dairy effluent. The experiment was carried out in a randomized complete block (5 x 2) with four green manures: Canavalia ensiformis (jack bean), Crotalaria spectabilis (Crotalaria-espectábilis), Lupinus albus (white lupine) and Pennisetum glaucum (millet) and one control (no green manuring), and two water sources used in fertigation (tap water and treated anaerobic effluent), with four replications. The effluent treated by anaerobic system was characterized biweekly throughout the experiment and were evaluated: foliar diagnosis of mini tomato, phytomass production of green manures and nutrient accumulation, productivity, chemical composition and fruit quality of mini tomato and water use efficiency. The highest levels of nitrogen were determined in the leaves of the single cherry tomato fertirrigated with tap water and for the cherry tomato in consortium with crotalaria-espectábilis fertirrigated with treated anaerobic effluent. The application of the treated dairy effluent adequately provided the nitrogen supply to the cherry tomato. The green manures, with the exception of millet, did not compete for nutrients with the cherry tomato, although, did not favor the productivity of the cherry tomato. The highest number of fruits occurred for the single crop and for the cherry tomato in consortium with white lupine. The fruits of the cherry tomato showed higher soluble solids contents when fertirrigated with treated dairy effluent. The crotalária-espectábilis and jack bean consortia had the greatest water use efficiencies in fruit production, and fertirrigated treatments with tap water showed higher WUE in comparison to fertirrigates with anaerobic effluent. The use of the treated anaerobic effluent of dairy reduced on average 90.89% of the application of nitrogen via fertilizer. It is possible to replace pure or potable water by treated dairy effluent in the cherry tomato fertirrigation.