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

Abstract

Lettuce cultivars in hydroponic system as a function of saline management applied at different times. The semi-arid region for presenting water with a high content of scarcity associated with the need to increase agricultural production, it becomes necessary for its use, and these waters may cause damage and consequently reducing crop production. It is proposed, in the work, to evaluate the use of saline water in the nutrient solution at different times of application in cultivation hydroponic of three lettuce cultivars. The experiment was developed in protected environment, adopting the split plot design with factorial 4 x 3 treatments, the level of electrical conductivity used in the nutrient solution was 5.0 dSm-1a applied in three periods (5, 10 and 15 days after DAT transplantation) and one control associated with three cultivars of curly lettuce (Venerando, Camila and Elba). O management of saline water in the nutrient solution has a negative effect on growth lettuce plants mainly in M1 and M2 and the control showed better growth. The Elba cultivar independent from management shows better performance in in relation to Veneranda and Camila. The management of saline water in the nutrient solution compromises absolute and relative growth rates mainly in M2 and M3, having this treatment greater reduction. Lettuce plants in the hydroponic system under Saline stress has lower chlorophyll content and relative water content in all managements The most affected employees were M2 and M3. Saline stress reduces gases with a greater reduction when M3 was used.