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The present study aimed to evaluate the initial growth of Passiflora edulis plants under water deficit and inundation. The work was carried out in a greenhouse covered with transparent plastic in pots with a capacity of five liters and filled with 5 kg of substrate composed of oxisol, sand and cattle manure in the proportion of 3:1:1, respectively. The experimental design used was completely randomized, with seven treatments and five repetitions; 30 days after emergence, the plants were irrigated with water equivalent to 25%, 50%, 75%, 100%, 125%, 150% and 175% of the pot capacity and the analyzes were performed on the 52nd day. The P. edulis plants under limitation and excess water showed high stomatal sensitivity to reduce the water. In addition, under water deficit, the plants showed bigger root growth to maximize water absorption from the soil, but in both stresses the plants demonstrated reduced vegetative growth, that implies retarded establishment, thus, demonstrating an average susceptibility to water deficit and inundation.

O presente estudo teve como objetivo avaliar a produtividade de plantas de pinhão manso cultivadas em diferentes espaçamentos. O trabalho foi conduzido no campo experimental da Universidade Estadual de Goiás em Latossolo Vermelho-Amarelo. Utilizou-se o delineamento experimental em blocos casualizados com três tratamentos (plantas cultivadas nos espaçamentos 3x1, 3x2 e 3x3 m) e seis repetições. A competição entre plantas de pinhão manso pouco afetou o crescimento vegetativo das plantas, no entanto, com o desenvolvimento dos frutos, drenos que mais demandam assimilados na planta, a competição por recursos abióticos contribuiu para redução da produtividade. Palavras-chave: Densidade de plantas; Jatropha curcas; rendimento de sementes.The present study aimed to evaluate the productivity of Jatropha curcas plants grown at different spacings. The work was conducted in the experimental field of the University of Goiás in Oxisol. We used a randomized complete block design with three treatments (plants grown in spacing 3x1, 3x2 and 3x3 m) and six replications. Competition between plants of Jatropha curcas had little effect on the vegetative growth, however, with the development of the fruit, drains demand more assimilated in the plant, the competition for abiotic resources in plants densest contributed to reduced productivity.

This study has shown the main issues related to the process design of Brazil nuts, supporting the necessity for research on new strategies to improve the quality of nuts. Also, the habit of eating Brazil nuts stored throughout the year may represent a risk to farmers.

Although soybean flowers are produced abundantly, a large number of flowers and young pods abort naturally. Abortion reduction may result in an increased number of pods, thus leading to a growth in grain yield. The objective of this study was to evaluate the effect of benzyladenine application on soybean pod abortion and, consequently, to increase the productivity of soybean cultivation. The soil of the experimental area is classified as oxisol. After soil analysis, fertilization and pH correction were performed according to technical recommendations for cultivation. Pioneer 98Y12 RR soybean was sown by mid-November, during the rainy season. Benzyladenine application at the end of flowering, with pods of about 1.5 cm length, provided a significant increase in productivity of the species for all used concentrations, with the treatment of 300 mg L-1 corresponding to the highest increase, around 11%. The increase in productivity was determined by the higher number of total pods fixed to the plants by reason of abortion reduction in the three canopy positions. Other factors that contributed to the increased productivity were the higher number of seeds per plant, higher weight and seed diameter. Benzyladenine application is a promising practice for getting high productivity in the cultivation of soybean.

Sorghum is an alternative crop to produce grains in the off-season in Brazilian Cerrado and the intercropping with Brachiaria species enable to produce dry matter on the soil surface for a longer time. However, there is limited information on Brachiaria ruziziensis seed density to be applied to intercropping with sorghum without causing decreases in sorghum grain yield. The objective of the study was to evaluate the seeding density of B. ruziziensis in different intercropped systems with grain sorghum grown after soybean harvest, in off-season cultivation, to produce grains and the effects of straw on the agronomic performance of the soybean crop in succession to intercropping. This study was conducted in the field during the 2014 off-season in Rio Verde, Goiás. The experimental design was complete randomized blocks in a 3×5 factorial arranged with four replications corresponded to intercropping on rows, inter-rows and broadcast sowing with the densities of 2, 4, 6, 8 and 10 viable pure seeds m -2 of B. ruziziensis. Monocultures of sorghum and these forage crop were also evaluated. The results demonstrated the absence of effects of intercropping systems and seeding density on the yield of sorghum grains and on the cultivation of soybean in succession. The intercropping was effective in producing straw on soil surface to Cerrado no-tillage system.

Os fungos micorrízicos arbusculares (FMAs) e a população microbiana do solo ocupam papel de destaque em amenizar os efeitos causados pelo estresse hídrico em diversas culturas, entretanto se faz necessário estabelecer parâmetros sobre a dinâmica da interação desses microrganismos com as plantas em condições de estresse. Diante do exposto, o trabalho teve por objetivo avaliar a micorrização e a respiração microbiana do solo cultivado com mudas de maracujá amarelo e pinhão manso submetidas a diferentes níveis de água. O experimento foi realizado em vasos na casa de vegetação localizada na Universidade Estadual de Goiás, unidade de Ipameri. O delineamento utilizado foi inteiramente casualizado, e analisado em um esquema fatorial 2 x 7 sendo duas espécies de plantas (maracujá e pinhão manso) e sete níveis de fornecimento de água (25%, 50%, 75%, 100%, 125%, 150% e 175%) em relação a capacidade de campo (CC) do solo com cinco repetições, totalizando 70 parcelas experimentais de cultivo. Foram avaliadas a respiração microbiana do solo (RM), número de esporos micorrízicos (ESP) e colonização micorrízica (CM). Em termos de RM os solos responderam de forma distinta a alteração da umidade do solo, onde a microbiota do solo com pinhão manso se mostrou mais adaptada até aos 175% da CC que do maracujá. A condição de excesso hídrico provocou uma diminuição no ESP do solo de ambas a culturas, porém com efeito sendo mais significativo na cultura do maracujá que apresentou uma média de 77,2 esporos 50 g-1 de solo. A CM do pinhão manso e do maracujazeiro foram afetadas negativamente com o aumento dos níveis de umidade do solo, porém o pinhão manso apresentou em média uma taxa de CM 38,5% maior que o maracujá. De maneira geral a microbiota do solo e os FMAs sob mudas de pinhão manso responderam melhor ao estresse hídrico.