Mecanismos de memória molecular na interação arroz/Gluconacetobacter diazotrophicus, sob estresse hídrico

Abstract

Brazil is responsible for annually producing about 11 to 13 million tons of rice (Oryza sativa L.), a cereal of great economic importance, and in the Brazilian Northeast, the production of red rice stands out. However, abiotic factors, such as water deficit due to drought, have negatively influenced the production of this grain. To minimize damage and maximize production, biotechnological tools have been used, such as plant growth promoting bacteria (BPCV) and molecular memory modification. Thus, the present work aimed to analyze the activation of memory controls in red rice plants inoculated with Gluconacetobacter diazotrophicus under recurrent water stress. Initially, inoculation was carried out using the PAL5 strain of G. diazotrophicus using the 405 EMBRAPA Meio Norte red rice cultivar, consisting of two conditions, non-inoculated seeds and inoculated seeds, after the process they were propagated. Subsequently, the plants were subjected to three conditions of water stress: daily irrigated; water deficit for 15 days in the vegetative phase (V3) and water deficit for another 15 days in the reproductive phase (R3); and plants cultivated under water deficit for 15 days in the reproductive phase (R3). The biochemical and molecular responses involved in the defense process against drought and the plant-G diazotrophicus interaction were analyzed. Inoculation with the bacteria G. diazotrophicus proved to be a potential tool against water stress in red rice. Red rice presents biochemical and molecular adjustments depending on the water availability of the environment in which it grows. However, under inoculation conditions with G. diazotrophicus such water stress conditions are mitigated. Red rice plants inoculated with G. diazotrophicus stand out for their molecular memory, with lower methylation values in key genes for responses to water stress.