Uso de peróxido de hidrogênio na aclimatação do sorgo ao estresse salino

Abstract

ABSTRACT The use of chemical conditioners, such as hydrogen peroxide (H2O2), is important for mitigating deleterious effects caused by salt stress on plants. This practice can increase the production of agricultural crops, including sorghum, in the Semiarid region of Brazil. In this sense, the objective of this study was to evaluate effects of different electrical conductivities of the irrigation water and H2O2 concentrations on plant growth and biomass accumulation of sorghum plants grown in the Semiarid region of Brazil. The experiment was conducted from November 2020 to January 2021 in a greenhouse at the Center for Agri-Food Sciences and Technologies of the Federal University of Campina Grande, in Pombal, Paraiba, Brazil. A randomized block experimental design was used, in a 4×4 factorial arrangement, consisted of four electrical conductivities of the irrigation water [0.30 (control), 1.50, 3.50, and 5.50 dS m-1] and four H2O2 concentrations [0 (control), 6, 12, and 18 µM], with three replications and one plant per plot, totaling 48 experimental units. Plant height, stem diameter, flag leaf length, and fresh and dry weights of leaves and stems were evaluated. The results showed that applying irrigation water with electrical conductivities higher than 1.50 dS m-1 decreases plant growth and biomass accumulation in sorghum plants. Treating sorghum seeds with H2O2 concentrations of up to 12 µM mitigates adverse effects caused by salt stress on sorghum plants subjected to the salinity levels evaluated in the present study.