Condicionamento de sementes com peróxido de hidrogênio atenua os danos causados pelo estresse salino em sorgo

Abstract

ABSTRACT Salinity affects physiological processes, such as photosynthesis, in various agricultural crops, such as sorghum, around the world. Thus, mitigating techniques such as priming seeds with hydrogen peroxide (H2O2) can increase plant tolerance to salt stress. Thus, the objective of present study was to evaluate the priming of seeds with hydrogen peroxide on gas exchange and shoot phytomass of sorghum grown under salt stress. The treatments were distributed in a randomized block design, in a 4 × 4 factorial arrangement, with four levels of electrical conductivity of irrigation water - (ECw- 0.3, 1.5, 3.5, and 5.5 dS m-1) and four concentrations of H2O2 (0, 6, 12, and 18 μM L-1), with three replications. The salinity of the water reduced gas exchange, shoot fresh and dry mass, in addition to shoot moisture content in sorghum plants. However, priming the seeds with H2O2 improved gas exchange and the accumulation of plant dry mass. Seed priming with H2O2 at dose of 8.2 µM increases the acclimatization of sorghum plants under salt stress.