The aim of this study was to evaluate and explicate the changes in the nitrogen compounds and enzyme activities in Sorghum bicolor plants (cv. Br-700) submitted to water deficit during vegetative, reproductive and maturation stages. The experimental design used was entirely randomized in factorial scheme, with two conditions (control and stress) combined with three stages (vegetative, reproductive and maturation). The nitrate level was increased at 180.6, 72.9 and 78.9% during the vegetative, reproductive and maturation stages, respectively. The total soluble amino acids and glycinebetaine increased only during vegetative and reproductive stages, if compared with control plants. However, besides protein levels during all stages, significant reductions were reported in nitrate reductase and glutamine synthetase activities; free ammonium presented decreases at 37.3 and 77.6% in vegetative and reproductive stages, respectively, when compared with control plants.

The aim of this study was to investigate the changes in photosynthetic pigments and carbohydrate contents on resistant and susceptible plants of Phaseolus vulgaris L. (cvs. Mexico 222 and Widusa) infected by Colletotrichum lindemuthianum race 23. The experimental design used was entirely randomized in factorial scheme, with 2 cultivars (Mexico 222 and Widusa) and 2 treatments (control and inoculated). The cultivar Widusa (susceptible) showed a significant reduction in photosynthetic pigments, and an increase in the total carbohydrates, sucrose and reducing carbohydrates, whereas the cultivar Mexico 222 (resistant) showed a significant change in the carotenoid and total carbohydrate contents.