Mitigação do estresse hídrico na fase vegetativa de amendoim rasteiro, com suplementação de piruvato.

Abstract

Peanut (Arachis hypogeae L.) is an oilseed with high economic and nutritional value, used in natura, industrialized or for oil production. Despite the increase in production in Brazil, drought remains a significant environmental challenge, causing water stress that affects crop yield and quality. This study aimed to evaluate the ecophysiology of creeping peanut (cv. IAC Caiapó) in the vegetative phase under water deficit and foliar application of pyruvic acid. The experiment was developed in a protected environment, belonging to the Academic Unit of Agricultural Engineering of the Federal University of Campina Grande - PB. The treatments resulted from the combination of two factors: Water condition (Control - irrigated plants and Water stress - irrigation suppression for 10 days in the vegetative phase) and five concentrations of pyruvic acid (0, 200, 400, 600 and 800 µM). The plants were distributed in a randomized block design, in a 2 x 5 factorial scheme, with five replicates, totaling 50 experimental units. Stomatal conductance, transpiration, internal CO2 concentration, CO2 assimilation rate, instantaneous carboxylation efficiency, relative water content, electrolyte leakage, photosynthetic pigments, main stem height, number of leaves and leaf canopy temperature were evaluated. It was found that water stress favored the reduction of physiological parameters and growth variables of creeping peanut. Supplementation with pyruvic acid alleviated the damage caused to the internal CO2 concentration and improved the CO2 assimilation rate, instantaneous carboxylation efficiency, total chlorophyll content and number of leaves. Given the effects of pyruvic acid, we recommend carrying out new tests under field conditions throughout the peanut crop cycle, for the adoption of this technology.