The Action of 24-epibrassinolide and Azospirillum Brasilense on Soybean Morphogenesis and Metabolism

Abstract

The search for more sustainable agricultural practices has driven the adoption of strategies that favor plant growth efficiently and with less dependence on chemical inputs. In this context, plant growth regulators, such as brassinosteroids, and growth-promoting microorganisms, such as Azospirillum brasilense, stand out for the beneficial effects they exert on the physiology and development of agricultural crops. The general objective of this work is to evaluate the effects of 24-epibrassinolide and inoculation with Azospirillum brasilense on the morphogenesis of soybean crops. The experiment was conducted in a greenhouse belonging to the Federal University of Maranhão (UFMA). The experiment was carried out between September and December 2023. Soybean seeds were used for the experiment. The experimental design used was completely randomized, in a 2x3 factorial scheme, with four replications. The first factor corresponds to seed inoculation (at the time of sowing) with Azospirillum brasilense and the absence of inoculation. The second factor corresponds to the application of three concentrations of brassinosteroids (0, 20, and 40 nM). The variables plant height, stem diameter, and number of leaves did not show a significant effect, while the length and diameter of the taproot showed an interaction effect. The combination of 24-epibrassinolides and Azospirillum brasilense offers a promising strategy to improve carbon and nitrogen metabolism in soybeans, contributing to increased productivity and crop sustainability.