ÍNDICES FISIOLÓGICOS E CRESCIMENTO DE PORTA-ENXERTOS DE CAJUEIRO SOB ESTRESSE SALINO E CONCENTRAÇÕES DE PROLINA

Abstract

In semi-arid region, the low availability of good quality water has become a serious problem for the expansion of agriculture, requiring the use of water with high levels of salts. In this context, the objective of this study was to evaluate the physiological indices and growth of cashew clones subjected to different salinities of water and exogenous application of proline. The study was carried out under greenhouse conditions in a randomized block design, distributed in a factorial 5 x 4 x 2, corresponding to five levels of electrical conductivity of the water - ECw (0.3; 1.0; 1.7; 2.4 and 3.1 dS m^-1), four proline concentrations - PC (0; 4; 8 and 12 mM) and two cashew clones (CCP 76 and Faga 11) with three replicates and two plants per plot. Irrigation with saline water limits the physiological indices of cashew rootstocks; however, the ECw up to 2.3 dS m^-1 promoted acceptable reductions of less than 10% in these variables. Clone CCP 76 stood out with greater allocation of phytomass. The application of proline at a concentration of 7.4 mM promoted a greater allocation of stem dry phytomass of the cashew rootstocks irrigated with saline water.