Cultivares de alface em sistema hidropônico em função do manejo salino aplicado em distintas épocas.

Abstract

Saline stress affects the growth and productivity of many plants. The alternate use of water can minimize the effects caused by salinity. The aim of this study was to evaluate the use of saline water at different times in the hydroponic cultivation of three cultivars of curly lettuce. a. The experimental design was in subdivided plots, in a 4 × 3 factorial arrangement, with four managements of the nutrient solution and a control (1 to 5 days after transplanting DAT (M1), 5 to 10 DAT (M2), 10 to 15 DAT (M3)) and three cultivars of curly lettuce (Camila, Veneranda and Elba). The management of the nutrient solution has a negative effect on the growth of lettuce plants, especially in management two. The Elba cultivar, regardless of management, performs better and is suitable for hydroponic cultivation with saline solution. Increasing the amount of saline solution reduced the chlorophyll content and relative water content in all the managements used. Salt stress reduces gas exchange with a greater reduction in management three, the greatest reductions were in the rate of net photosynthesis and transpiration rate.