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The aim of this study was to evaluate the development, yield and its components of soybean sown in hill drop method with variation in hole spacing, compared to the conventional sowing method in lines. The experiment was conducted in a randomized block design, with six treatments and four replications, using the variety M7739 RR IPRO with four plans per hole. The treatments consisted of population variation from 50 to 150% of the recommended one, obtained by the holes spacing alteration and a control sowed in lines with the recommended population. The control was compared to the other treatments using the Dunnett test and the hole spacing effect was evaluated by regression. The cultivar 7739 RR IPRO responds to hill drop sowing, obtaining even in lower populations, yields similar to the conventional sowing in lines. The highest yields in the hill drop sowing method are obtained in the higher populations, with a linear decrease in yield with an increase in hole spacing. Increasing hole spacing increases the number of pods and branches and reduces leaf cover, light interceptcion, plant height and first pod height.

The use of animal residues from poultry as an organic fertilizer is a sustainable way to dispose of the production system, but there is still a need for further studies on the dynamics of nutrient availability. The objective of this work was to evaluate the use of poultry litterassociated with nitrogen fertilizer in the corn(Zea mays) crop and the availability of nitrogen from the residueduring three years of cultivation. The factors consisted of poultry litterdoses (2, 5 and 8 Mg ha-1) and nitrogen doses (0, 50, 100, 150, 200 kgha-1). The control group received mineral fertilizer at the dose of 120, 80 and 20 kg ha-1of P2O5, K2O and N, respectively, and covered with 200 kg ha-1of N. SPAD index readings, plant height, ear height, yield, one hundred grain mass and number of grains per spike were made.The highest doses of poultry litter(5 and 8 Mg ha-1) in three consecutive years, even without N broadcast, propitiates similar yieldto the mineral fertilizer control in the corn crop, thus, the poultry litter is an alternative viable in long-term corncrop fertilization.

The guava (Psidium guajava L.) belongs to the family Myrtaceae, it originates of Tropical America and it is distributed throughout the Brazilian territory. The production phase of the seedlings it is fundamental importance in the productive process, because seedlings better quality directly influence in success and final production. For this, it is made necessary to use substrates that meet the exigencies of the culture. In this way, the objective was to evaluate the germination of 'Cortibel' guava seeds and initial development of the plants in different substrates. The seeds were withdrawals of fruits guava physiologically ripe of the Cortibel cultivar, were then washed and air dried, next were planted in 1,5 L bags drilled, in September 2017 on two types of substrate (sand and commercial substrate Bioplant®) the sacks being kept in a screened nursery with 60% light interception. The design was completely randomized, with the substrates composing the treatments (washed sand and commercial substrate Bioplant®) and nine replications. Each replicate was formed by five bags totaling 45 experimental units for each treatment. In each perforated bag containing the treatments (substrates) were placed 5 seeds. Germination was accompanied along the throughout experimental period and at 129 days after sowing (DAS) was the period in which emergence of seedlings occurred. It was characteristics plant height, stem diameter and number of leaves were evaluated. The sand substrate provided a higher germination rate in relation to the Bioplant® substrate, however, the use of the Bioplant® commercial substrate presented higher initial development, with higher values of plant height and stem diameter, being the substrate indicated for the production of seedlings of guava 'Cortibel' by seeds.

Knowledge of the genetic variability among genotypes of bushy cashew is important to establish strategies for pre-breeding and use in breeding program. The objective of this study was to evaluate the genetic diversity of bushy cashew by means of the evaluation of physical, chemical and physicochemical characteristics of cashew apples and cashew nuts. The work was carried out with cashew nuts and cashew apples collected in the harvest of 2016 of genotypes in the “ex situ” biological collection of Anacardium humile A. St.-Hil. in the area of genetic resources of the Universidade Federal de Goiás - Regional Jataí. The results were submitted to descriptive analysis and multivariate analysis, estimating the mean Euclidean distance obtained from the fruiting attributes analyzed. The measure of similarity and custering of the provenances was done by the optimization algorithm of Tocher and dendrograma UPGMA. There was a coincidence of clusters, which confirms the distribution of genetic diversity of the genotypes in the germplasm bank of Anacardium humileA. St.-Hil. evaluated. The results obtained can be used for the selection of individuals of the species in future works of breeding and conservation of the specie. Resumo O conhecimento da variabilidade genética entre genótipos de Cajuzinho-do-cerrado é importante para estabelecer estratégias de pré-melhoramento e uso em programa de melhoramento. Objetivou-se com este trabalho avaliar a diversidade genética de Cajuzinho-do-cerrado por meio da avaliação de características físicas, químicas e físico-química de frutos e pseudofrutos. O trabalho foi realizado com frutos e pseudofrutos coletados na safra de 2016 dos genótipos da coleção biológica “ex situ” de A. Anacardium humileSt.-Hil. na área de recursos genéticos da Universidade Federal Goiás - Regional Jataí. Os resultados foram submetidos à análise descritiva e à análise multivariada estimando-se a distância euclidiana média obtida a partir dos atributos da frutificação analisados. A medida de similaridade e agrupamento das procedências foi feita pelo algoritmo de otimização de Tocher e dendrograma UPGMA. Houve coincidências entre os agrupamentos, o que confirma a distribuição da diversidade genética dos genótipos no banco de germoplasma de Anacardium humile A. St.-Hil. avaliado. Os resultados obtidos podem ser utilizados para a seleção de indivíduos da espécie em futuros trabalhos de melhoramento e conservação da espécie.

Soil chemical and physical attributes are important in any agricultural cropping system, but in precision agriculture they are more relevant due to the possibility of application using different management practices along a produc­tion field. However, the correlation between these attributes has been little explored in the delineation of man­agement zones. This work aims to maximize the use of joint spatial variability for soil attributes. Its secondary objectives were 1) reduction of spatial variability dimensionality among all attributes and 2) assessment of agree­ment between univariate and multivariate management zones. The management zones resulting from the inter­polation of attribute values, as well as from the scores of each of the three main components, were delineated using the Fuzzy c-means algorithm. The fuzzy performance and modified partition entropy indexes were used to determine the optimal number of management zones. The Kappa index was used to evaluate the agreement of management zones obtained from attributes with those obtained from principal components. By using principal component analysis, it was possible to reduce the dimensionality of the number of variables that contribute to the joint spatial variability existing in the study area. There was no complete agreement between the uni- and multi­variate management zones outlined, which is why further studies on the subject are needed.

To map the spatial variability of a field to define the variable rate application, an intensive sampling of the soil-plant system is necessary. The apparent soil electrical conductivity (ECa) has been used for soil mapping because it correlates well with soil attributes, allows for dense sampling and can be obtained at low cost. However, ECa is influenced by soil moisture content, and the variability of this attribute can reduce the reliability of the ECa maps to explain the physical and chemical soil attributes. The objective of this study was to identify conditions that maximize the correlations between the ECa and the soil attributes. The results show that the mean soil moisture content of soil sampled on different dates was correlated with the mean of the ECa. The ideal time for measuring ECa occurred when the mean moisture content of the soil was higher. In this condition, the coefficient of variation for the soil moisture content was lower, there was no correlation between ECa and soil moisture content, and ECa was more correlated with other soil attributes evaluated in this work. Para mapear a variabilidade espacial de um campo e definir a aplicação em taxa variável, uma amostragem intensiva do sistema solo-planta é necessária. A condutividade elétrica aparente do solo (ECa) tem sido utilizada para o mapeamento do solo, pois correlaciona-se bem com os atributos do solo, permite a amostragem densa e pode ser obtida a baixo custo. No entanto, o ECa é influenciada pelo teor de água do solo, e a variabilidade desse atributo pode reduzir a confiabilidade dos mapas de ECa para explicar os atributos físicos e químicos do solo. O objetivo deste estudo foi identificar as condições que maximizem as correlações entre a ECa e os atributos do solo. Os resultados mostram que o teor de água médio do solo amostrado em diferentes datas foi correlacionado com a média da ECa. O momento ideal para medir ECa ocorreu quando o teor de água médio do solo foi mais elevado. Nesta condição, o coeficiente de variação para o teor de água do solo foi menor, não houve correlação entre ECa e o teor de água do solo, e ECa foi mais correlacionado com outros atributos do solo avaliados nesse trabalho.

The propagation of gabirobeira is carried out by seeds. However, the recalcitrance and not tolerance of the seeds to the storage compromise the formation of seedlings. Thus, the propagation by cuttings can be an option, being able to provide significant results in different seasons. The objective of this work was to evaluate the vegetative propagation by stem cuttings of two species of gabirobeira (Campomanesia adamantium and Campomanesia pubescens) associate to indolbutyric acid (IBA) at differents seasons of the year. Cuttings of the two species were obtained in the 4 seasons and concentrations of 0, 2000, 4000, 6000 and 8000 mg L-1 of IBA were used, by immersion in the solution for 15 seconds and sequentially staked on trays containing a sand substrate. Sixty days after experiments were set it was evaluated the percentage of cuttings with shoots, live cuttings, dead cuttings, cuttings with calluses and rooted cuttings. A completely randomized design with 5 treatments, 4 replicates and 8 cuttings per plot was adopted. During the whole experiment, the greenhouse, substrate and cutting leaves temperature was monitored. The use of IBA did not promote adventitious rhizogenesis, but provided a high percentage of survival for the species Campomanesia adamantium and Campomanesia pubescens by stem cuttings during the spring season.

Because it is a species of tropical climate, the passion fruit is distributed widely in South America, mainly in Brazil. Its cultivation represents approximately 95% of the commercial orchards of the country, nevertheless, it presents productivity below its productive potential, being necessary to obtain cultivars adapted to the climate of the regions of culture. The objective of this work was to evaluate the quality of the fruit pulp of yellow passion fruit produced in Jataí-GO as well as the correlations between some physical and chemical characteristics. The fruits were collected in an experimental orchard and sectioned transversely to obtain the pulp. The characteristics of acidity, vitamin C content, soluble solids content, soluble solids/acidity ratio (Ratio), and pulp color parameters were evaluated through the coordinates L*, a*, b*, C* and h* of yellow passion fruit and of the cultivar FB 200. Data were analyzed by means of analysis of variance and Pearson’s correlation at 5% of significance with the aid of the statistical program Rbio. It is concluded that the characteristics of the fruits of the cultivar FB200 differed from the fruits of yellow passion fruit and that these characteristics correlated significantly and positively.

O objetivo deste trabalho foi avaliar a demanda energética de um protótipo de um subsolador com torpedo para inserção de material poroso em drenos. Os testes de avaliação do desempenho do protótipo foram efetuados em uma área experimental da Universidade Federal de Viçosa, localizadas no município de Viçosa-MG. O material poroso utilizado foi a casca de arroz. Foi mensurada a potência requerida e consumo de combustível. O delineamento experimental utilizados foi o fatorial, que consistiu em 2 velocidades e 4 profundidades com 3 repetições. O solo apresentou um perfil argiloso, caracterizado como Podzólico Vermelho-Amarelo. O maior requerimento de força pelo implemento foi de 13711,1 N e a maior potência de 17,85 kW. Esses valores foram observados para a velocidade de 4,9 km h-1, na profundidade de 0,60 m. A força média requerida pelo protótipo foi menor do que a encontrada na literatura. A média da potência requerida pelo implemento foi 9,98 kW, e pelo conjunto trator-implemento de 12,26 kW. A relação força de tração/profundidade de trabalho apresentou-se dentro do limite estabelecido pela ASAE para solos argilosos. This study was done to evaluate energy demand of a prototype subsoiler with expander to insert porous materials into drains. The study was done in an experimental area of the Federal University of Viçosa, Viçosa-MG. Fuel consumption and power requirement were measured using rice hull as the test porous material. The experiment was done with three replications in the factorial design, consisting of two speeds and four depths. The clayey soil profile was characterized as red-yellow podzol. The maximum force demanded by the prototype was 13711.1 N with maximum power of 17.85 kW. at the speed of 4.9 km.h -1 and the depth of 0.60 m. The mean force required by this prototype was lower than that reported in the literature. The average power required by the subsoiler was 9.98 kW, and that of the tractor-prototype combine was 12.26 kW. The tensile strength / work depth ratio was within the limits established by ASAE for clay soils.

Objetivou-se com este trabalho, avaliar as perdas quantitativas ocorridas na colheita mecanizada do milho cultivado em espacamentos reduzido e convencional. O delineamento experimental foi o de blocos casualizados com tres repeticoes em esquema fatorial (2 x 3 x 3), sendo dois espacamentos ( 0,45m e 0,90m): tres velocidades da colhedora (1,8 km.h-1 3,5 km.h-1 e 4,1 km.h-1) e tres aberturas do concavo (25 mm, 30 mm e 35 mm). Para os tratamentos onde o espacamento entre linhas foi de 0,45 m, a colhedora trabalhou com uma alimentacao de duas linhas entre os divisores de linha da plataforma de colheita enquanto nos tratamentos onde o espacamento foi de 0,90 m, a colhedora trabalhou com uma alimentacao de uma linha entre os divisores de linha da plataforma. A populacao de plantas foi a mesma para os dois espacamentos utilizados no experimento. As perdas naturais foram maiores nos tratamentos com espacamento convencional, porem as perdas na plataforma de colheita apresentaram os menores valores utilizando esse espacamento na velocidade de 3,5 km.h-1. As maiores perdas ocorridas nos mecanismos internos da colhedora ocorreram quando se utilizou abertura do concavo de 30 mm a uma velocidade de 3,5 km.h-1. As perdas totais representaram 8,2% e 7,3% da produtividade media nos espacamentos de 0,45 m e 0,9 m respectivamente.

The objective of this study was to evaluate the quantitative losses occurred in the mechanical harvesting of the corn grown in conventional and reduced gaps. The experimental design was randomized blocks with three replications and treatments distributed in a factorial (2 x 3 x 3), and two spacings (0.45 m and 0.90 m), three speeds of the combine (1.8 km.h-1 3.5 km.h-1 and 4.1 km.h-1) and three openings of the concave (25 mm, 30 mm and 35 mm). For treatments where the spacing was 0.45 m, the harvester worked with a power of two lines dividing line between the platform crop while in treatments where the spacing was 0.90 m, the harvester worked with a power dividing line between a line of platform. The plant population was the same for the two spacings used in the experiment. The natural losses were higher in the conventional spacing, but the header losses of harvest had the lowest use this space at a speed of 3.5 km.h-1. As maiores perdas ocorreram nos mecanismos internos da colhedora ocorreu quando se utiliza a abertura côncava de 30 mm a uma velocidade de 3,5 km.h-1. Total losses accounted for 8.2% and 7.3% of the average productivity in the gaps of 0.45 m 0.9 m respectivelyObjetivou-se com este trabalho, avaliar as perdas quantitativas ocorridas na colheita mecanizada do milho cultivado em espaçamentos reduzido e convencional. O delineamento experimental foi o de blocos casualizados com três repetições em esquema fatorial (2 x 3 x 3), sendo dois espaçamentos ( 0,45m e 0,90m): três velocidades da colhedora (1,8 km.h-1 3,5 km.h-1 e 4,1 km.h-1) e três aberturas do côncavo (25 mm, 30 mm e 35 mm). Para os tratamentos onde o espaçamento entre linhas foi de 0,45 m, a colhedora trabalhou com uma alimentação de duas linhas entre os divisores de linha da plataforma de colheita enquanto nos tratamentos onde o espaçamento foi de 0,90 m, a colhedora trabalhou com uma alimentação de uma linha entre os divisores de linha da plataforma. A população de plantas foi a mesma para os dois espaçamentos utilizados no experimento. As perdas naturais foram maiores nos tratamentos com espaçamento convencional, porém as perdas na plataforma de colheita apresentaram os menores valores utilizando esse espaçamento na velocidade de 3,5 km.h-1. As maiores perdas ocorridas nos mecanismos internos da colhedora ocorreram quando se utilizou abertura do côncavo de 30 mm a uma velocidade de 3,5 km.h-1. As perdas totais representaram 8,2% e 7,3% da produtividade media nos espaçamentos de 0,45 m e 0,9 m respectivamente

Nowadays the passion fruit plant can be irrigated with any one of the methods available: surface, sprinkler and drip irrigation. In the last method there is possible to apply fertilizers through water, what increases the efficiency and reduces the labor, allowing to turn

Neste estudo foram avaliadas seqüências ECF e TCF para o branqueamento de celulose de fibras secundárias destintadas provenientes de uma mistura de composição conhecida de lixo de escritório (MOW) e produzidas em planta piloto. A polpa foi branqueada a um nível mínimo de alvura de 78% ISO, sendo que o requerimento de reagentes e as principais propriedades da polpa foram avaliadas. Dentre as seqüência ECF, a mais atrativa foi a DEDD que apresentou o mais baixo custo e ainda eliminou toda a fluorescência e grande parte da coordenada de cor b* da polpa. As seqüências ECF resultaram em polpas de alta viscosidade em relação às convencionais. A seqüência TCF com ozônio mais atrativa foi a Q(PO)(ZQ)(PO) que se mostrou flexível quanto ao teto de alvura, além de reduzir significativamente a coordenada de cor b* e ligeiramente a fluorescência da polpa. A melhor seqüência TCF sem-ozônio Q(PO)Q(PO) apresentou-se pouco flexível quanto ao teto de alvura e teve pouco efeito na fluorescência e coordenada de cor b* da polpa. As viscosidades finais das polpas, branqueadas pelos processos TCF, foram aceitáveis. Os resultados de rendimento, para os processos avaliados nesse estudo, foram afetados negativamente por estágios alcalinos, como O, P e (PO), em alta temperatura. In this study, ECF and TCF bleaching processes were evaluated for the bleaching of a deinked mixed office waste (MOW) pulp sample produced in a pilot plant. The sample was bleached by all processes to a target brightness of 78 % ISO minimum. The results were interpreted on the basis of chemical cost to reach the target brightness, bleaching yield and bleached pulp quality as measured by viscosity, fluorescence and b* color coordinate. Among the ECF sequences, the mosattractive was the DEDD which showed the lowest chemical cost and produced bleached pulp of high quality as measured by viscosity, fluorescence and b* coordinate. The best TCF sequence with ozone was the Q(PO)(ZQ)(PO) which resulted in very high brightness ceiling. This sequence decreased moderately the pulp b* coordinate and viscosity and slightly its fluorescence. Among the TCF sequences without ozone the Q(PO)Q(PO) was the most effective but showed poor flexibility with regard to brightness ceiling. This sequence had little effect on pulp viscosity, fluorescence and b* coordinate. For all three bleaching processes, it was determined that process yield is negatively affected by hot alkaline stages such as O, P and (PO).

Buscou-se, com este estudo, estimar, através do uso da cokrigagem, valores de cálcio e magnésio, utilizando como co-variável valores de pH. Em um Latossolo Vermelho Distroférrico, amostrou-se a camada de 0-0,2 m, utilizando grade de 25 x 25 m, totalizando 60 pontos em 5,02 ha. Realizou-se, inicialmente, análise descritiva e de correlação e, posteriormente, análise geoestatística, para identificar a dependência espacial das variáveis estudadas. Utilizando a técnica da cokrigagem, os valores de pH mostraram-se eficientes na estimativa de teores de Ca e Mg, devido a elevada correlação entre esta co-variável e as variáveis a serem estimadas. Sought, with this study, estimating, through the use of cokriging, values of calcium and magnesium, using as covariate pH. In a Rhodic Hapludox, sampled the layer of 0-0.2 m, using the grid of 25 x 25 m, totaling 60 points from 5.02 ha. Was held, initially, descriptive analysis and correlation, and subsequently, geostatistical analysis to identify the spatial dependence of variables. Using the technique of cokriging pH values were efficient in the estimation of Ca and Mg, due to the high correlation between this covariate and the variables to be estimated.

The aim of this work was to describe the weed spatial variability in a no-tillage system area in Jatai, GO, Brazil. A regular grid was used on a 25 hectares field accomplishing 36 sample points. The total shoot dry matter of weeds was determined on an area of 0.5 m2 and also separated on broadleaf and grassy types. Images of the sample area were sorted by a supervised classifier into three classes: straw, leaves and uncovered. The soybean leaves were manually segmented from the leave class. The images were also processed using an automatic threshold method, separating the leaves from the background. On the processed images were calculated the covered areas by each class. All the variables were submitted to correlation and geostatistical analysis. A significant correlation was verified between covered area by plants and the shoot dry matter. The supervised classification and the automatic threshold method achieved similar results. When the soybean leaves was segmented, the calculation of the broadleaf weed infestation was improved. Spatial dependence was only verified when the two types of weeds were studied separately.