Selênio na mitigação dos efeitos do déficit hídrico em genótipos de arroz de terras altas

Abstract

Rice (Oryza sativa) is one of the most produced and consumed cereals in the world, being the main food for more than half of the world's population (FAO, 2023). In recent years, the research group on Genetic Improvement of Highland Rice, in partnership with EMBRAPA Arroz e Feijão and EPAMIG Sul de Minas, developed projects aimed at biofortification in highland rice, with the aim of serving as an ally in the combating malnutrition, hidden hunger in the world and highlighting the potential of Se to promote promising changes in the physiological system of plants under water stress conditions. The combination of these benefits favors the acceptance and dissemination of the strategy among rural producers. Therefore, the objective was to verify the capacity and potential of agronomic biofortification with selenium in minimizing the impacts caused by water stress during the development of upland rice in the field. The experiment was structured in a randomized block design with three lines belonging to the Cultivation Value and Use trial of the MelhorArroz UFLA program and four treatments, which consisted of: application of selenium via soil in top dressing with enriched urea, single foliar application of Se, foliar application of Se divided into two and control (without the application of Se). The same experiment was installed in two management systems: without irrigation and with supplemental irrigation via sprinklers. Data relating to grain height, income and yield, number of days to flowering (NDFL), Se content in the grain, productivity, sterility of grains in the panicle and mass of 100 grains were evaluated and analyzed. The observed results were subjected to analysis of variance using Software R at 5% probability. It was found that the BRS Esmeralda and ERF 221-16 genotypes presented the best results in response to biofortification and expression in environmental conditions under water stress. Soil application presented the highest averages for Se content in grains and the lowest averages for sterility, especially in the system without supplementary irrigation, being the most suitable for obtaining biofortified grains and gains in the phenotypic performance of the genotypes.