Fisiologia e produção de Quiabeiro sob salinidade da água de irrigação e adubação potássica.

Abstract

The scarcity of water resources in recent years has become a limiting factor for crop production, which may compromise the yield of plants, especially in okra, however, when cultivated in the semi-arid region, characterized by waters with high levels of salts, it becomes necessary the use of adequate management of resources in order to guarantee the sustainability of the production system. Thus, the objective is to evaluate gas exchange, chlorophyll a fluorescence and okra production components under water salinity and potassium fertilization doses. The experiment was carried out in randomized blocks in a 5 × 5 factorial scheme, in which the factors were constituted by five levels of salinity of the irrigation water (0.3, 1.3, 2.3, 3.3 and 4.3 dS m-1) and five doses of potassium (50, 75, 100, 125 and 150% of the K2O recommendation) where the dose of 100% refers to 150 mg of K2O kg-1 of soil, with three replications and one plant per plot. The gas exchange and chlorophyll a fluorescence were compromised by the increase in the electrical conductivity of the irrigation water from the level of 1.5 dS m-1. Potassium fertilization reduces the deleterious effects of salt stress on stomatal conductance, CO2 assimilation rate and instantaneous carboxylation efficiency of okra plants