Faced with the need for higher yields and lower costs in salinized areas, organic fertilizers (like bovine biofertilizers) have been widely adopted in agriculture. In that context, the objective of this study was to evaluate the effects of bovine biofertilizer and saline irrigation water, on cowpea gas exchanges and productivity. The research was conducted at the Fazenda Experimental do Vale do Curu, Pentecoste, Ceará, Brazil, from November 2010 to January 2011. The plants were disposed in randomized blocks, in a split-plot design with four

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

III RESUMO Esta nota tem por objetivo relatar o ataque de larvas do coró-das-pastagens, Diloboderus abderus

RESUMOOs resíduos de caranguejo apresentam potencial como adubo orgânico. Buscou-se neste trabalho, avaliar os efeitos da aplicação de resíduo de caranguejo Uçá na salinização do solo, no crescimento e nos teores de clorofila e solutos orgânicos e inorgânicos de plantas de melão. O experimento foi conduzido em casa de vegetação no período de maio a junho de 2010. Utilizaram-se oito tratamentos correspondendo às percentagens de 0, 1, 3, 5, 10, 20 e 30% de resíduo de caranguejo e um tratamento contendo adubação mineral (solução de Hoagland), todos com seis repetições. Trinta dias após o plantio foram avaliados em extrato solo : água (1:1) o pH, a condutividade elétrica (CE) e os teores de Na + e K + . Nas plantas foram avaliados a produção de massa seca da parte aérea, área foliar, massa seca da raiz e os teores foliares de clorofila e de solutos orgânicos e inorgânicos. O incremento nas concentrações de resíduos de caranguejo aumentou significativamente os valores de pH, CE, Na + e K + do solo. Foram observadas tendências quadráticas para as variáveis de crescimento e os teores de clorofila na planta. O aumento na CE e no teor de Na + contribuiu para reduzir o crescimento das plantas nos níveis mais elevados de resíduos de caranguejo. Palavras-chave: adubação, Ucides cordatus, Cucumis meloEffects of crab residue in soil salinization and development of melon ABSTRACT The residue of crab show potencial as organic fertilizer. This study evaluated the effect of applying concentrations of residue of crab Uçá in sanilization of soil, on growth, chlorophyll and organic and inorganic solutes in melon. This experiment was conducted under greenhouse conditions from May to June in 2010. Eight treatments were used corresponding to percentage of 0, 1, 3, 5, 10, 20 and 30% crab residue and a treatment containing mineral fertilizers (Hoagland solution), each with six replications. Thirty days after sowing in the soil : water (1:1) extract: pH, electrical conductivity (EC), and K + and Na + were evaluated. In plants dry mass of shoot, leaf area, root dry mass and leaf contents of chlorophyll and organic and inorganic solutes were evaluated. The increase in concentrations of crab residue significantly increases the pH, EC Na + and K + in the soil. Quadratic trends were observed for growth parameters and chlorophyll contents in the plants. The increase in the EC and the levels of Na + contributed to reduce plants growth in the higher levels of crab residue.

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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