Plasticidade fenotípica do feijão-caupi BRS Itaim sob restrição hídrica e Seed Priming com PEG 6000 e silício.

Abstract

The Brazilian Northeast region is characterized by its high variations in solar radiation levels and high air temperatures, harming the growth of cowpea, in this sense, there is a need for research that uses strategies to mitigate the stresses caused by water restriction. The objective was to induce water deficit tolerance in cowpea, cultivar BRS Itaim, from application of seed priming with polyethylene glycol 6000 and silicon. An experiment was conducted in the field using an entirely randomized design, with two irrigation rates (W50 and W100% of ETo - Reference Evapotranspiration) and six combinations of seed priming – SP (Ψ0 + 0Si, Ψ0 + 200Si, Ψ-0,4 + 0Si, Ψ-0,4 + 200Si, Ψ-0,8 + 0Si e Ψ-0,8 + 200Si), with four replications. Petiole water potential, relative leaf water content, cellular electrolyte leakage, proline content, superoxide dismutase activity, ascorbate peroxidase and total soil dry matter were evaluated. Data were submitted to analysis of variance and means comparison tests. It was found that seed priming with polyethylene glycol 6000 and silicon attenuates water stress through the homeostasis of water relations, osmotic adjustment and antioxidant mechanism of cowpea cultivar BRS Itaim.