RESUMOObjetivou-se com este trabalho avaliar o efeito da interação entre salinidade e espaçamento de plantio em plantas de milho (Zea mays L.) Híbrido AG 1051. Utilizou-se o delineamento em blocos ao acaso, em arranjo fatorial 3 x 2, sendo três espaçamentos entre fileiras (0,5, 0,7 e 0,9 m) e dois níveis de salinidade da água de irrigação (0,8 e 5,0 dS m -1 ), com 5 repetições. As variáveis analisadas foram: fotossíntese (A), radiação fotossinteticamente ativa (RFA), altura da planta, massa seca da parte aérea (MSPA), índice de área foliar (IAF), área foliar (AF), e teores foliares de carboidratos, N-aminossolúveis, Na + e K + . As taxas de fotossíntese líquida não diferiram significativamente em decorrência dos espaçamentos nem da salinidade da água de irrigação. A RFA interceptada pelas folhas basais do milho foi maior no espaçamento com 0,9 m, porém não houve diferença entre as plantas estressadas e não estressadas, com relação à radiação interceptada pelas folhas e as taxas fotossintéticas. Embora a salinidade tenha afetado os níveis de carboidrato e de sódio nas folhas, as maiores diferenças foram relacionadas ao espaçamento de plantio e à idade da folha avaliada. De modo geral, o adensamento do cultivo de milho não minimizou os efeitos deletérios da salinidade no crescimento das plantas. Palavras-chave: estresse salino, fotossíntese, Zea maysPhysiology and growth responses of maize subjected to salt stress in different cultiving spacings ABSTRACT The objective of this work was to evaluate the effect of interaction between salinity and plant spacing on maize (Zea mays L.) hybrid AG 1051. A randomized block in a 3 x 2 factorial was used, with three row spacings (0.5, 0.7 and 0.9 m) and two levels of salinity of irrigation water (0.8 and 5.0 dS m -1 ), with five replications. The variables analyzed were: photosynthesis (A), photosynthetically active radiation (PAR), plant height, shoot dry mass (SDM), leaf area index (LAI), leaf area (LA), content of carbohydrate, soluble N-amines, Na + and K + . The rates of net photosynthesis did not differ significantly neither as a result of plant spacings nor the salinity of irrigation water. The PAR intercepted by the basal leaves of maize was higher in the spacing of 0.9 m, but no difference between stressed and unstressed plants in relation to the radiation intercepted by leaves and photosynthetic rates was observed. Although salinity affected the levels of carbohydrates and sodium in leaves, the greatest differences were related to plant spacing and leaf age evaluated. In general, the densification of maize cultivation did not minimize the deleterious effects of salinity on plant growth.

This study aimed to evaluate the effect of management strategies of irrigation with saline water on growth and yield of cowpea and sunflower in a crop rotation. The experiment was conducted in randomized blocks

Stapled haemorrhoidopexy transiently decreases rectal compliance and sensitivity threshold in young male patients.

An adequate mineral nutrition is essential for the development and productivity of pineapple. However, little is known about the nutritional and metabolic changes that occur in this crop in response to micronutrient deficiency or excess, particularly on tropical conditions. Thus, the objective of this study was to evaluate the application effects of micronutrients in soil and in leaf on biochemical responses of leaves during the development cycle of the pineapple crop. Samples were collected at 3, 6, 9, 12, and 17 months after transplantation. Leaf soluble carbohydrates and N-aminosoluble compounds were determined, as well as variations in the titratable acidity and pH. The soil and leaf micronutrient application increased the concentrations of carbohydrates and N-aminosoluble and reduced the leaf pH, and the changes were more significant in the last sampling (17 months after transplantation). Reductions in concentrations of carbohydrates and increase in the titratable acidity of the pineapple leaves collected at the end of the night were also observed, a fact that reflects the metabolism of Crassulacean acid metabolism species. The strategy of micronutrient application contributes positively to alter the metabolism of plants of pineapple cv. Victoria, especially during flowering and fruit development.

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