Ácido salicílico e extrato de Moringa oleifera como atenuadores do estresse salino em cultivares de gergelim

Abstract

Sesame is an oilseed with relevant nutritional value and socioeconomic potential in Brazil, especially the Brazilian semi-arid region, however, limiting factors to its growth and development in this region are due to the occurrence of waters with a high content of salts, therefore, research aimed at the use of technologies that can reduce the adverse effects of salinity on plants, if necessary. Given the above, the objective was to evaluate the effect of salicylic acid (SA) and M. oleifera leaf extract (MOLE) on sesame cultivars BRS Anahí and BRS Seda, subjected to saline stress. The treatments were distributed in a completely randomized design, combined in a factorial scheme (2x4x4), resulting in 32 treatments with four replications each, totaling 128 experimental plots, with two sesame cultivars BRS Anahí and BRS Seda, four seed primings, distilled water (control) ; AS (10 ppm); (EFM 8.96% (m/v)) and AS (10 ppm) + EFM 8.96% (m/v), four foliar sprays, distilled water (control); AS (10ppm); (EFM 8.96% (m/v)) and AS (10 ppm) + EFM 8.96% (m/v). The experiment data were submitted to analysis of variance by the F test up to 5% error probability. When significant, the means of seed priming and spraying were compared using the Tukey test (P<0.05) using the statistical software SISVAR-ESAL 5.6 (FERREIRA, 2019). The salinity of water irrigated with 5 dS m-1 causes a negative effect on the growth and development of sesame cultivars, and the number of pods for cv. BRS Seda, and number of leaves and leaf area for cv. BRS Anahí the most affected variables. The seed priming (AS+EFM) x foliar spraying (EFM) causes greater growth in plant height, stem diameter, number of leaves, leaf area and number of pods of sesame cv. BRS Anahi. Seed priming (EFM) x foliar spraying (SA+EFM) stimulates a greater increase in stomatal conductance, CO2 assimilation rate, intrinsic water use efficiency and instantaneous carboxylation efficiency of sesame cv. BRS Anahí, and seed priming (AS) x foliar spraying (AS+EFM) provided a greater increase in stomatal conductance, CO2 assimilation rate, transpiration and instantaneous carboxylation efficiency for sesame cv. BRS Silk. The interaction SP-AS+EFM x PU-EFM promotes the best development and production of sesame cultivars, submitted to irrigation with saline waters.