AVALIAÇÃO DO POTENCIAL DO BACILLUS ARYABHATTAI EM MITIGAR O ESTRESSE HÍDRICO NA CULTURA DA SOJA

Abstract

Water scarcity is one of the main obstacles to soybean productivity and can result in losses of 25% to more than 50% - which represents a reduction of approximately 15 to 35 sacks per hectare -, depending on the temperature and the stage of development of the plant. The objective of this study was to evaluate the potential effect of inoculation of Bacillus aryabhattai on soybean development and productive performance under four irrigation regimes The present work was carried out at the Federal Institute of Education, Science and Technology Goiano - Campus Cristalina, located in the municipality of Cristalina-GO. The experimental design used was that of randomized blocks (DBC), according to a 4 x 2 factorial scheme with four replicates totaling 32 plots. The first factor was composed of 4 levels of water tension in the soil, - 15, - 25, - 35 and - 45 kPa, denominated T1, T2, T3 and T4 respectively, and these tensions determined the definition of the irrigation moment, being applied in stages R2 and R5, and the levels of the second factor were composed by inoculation and non-inoculation of B. aryabhattai, presented as CB and SB, respectively. The evaluated parameters were: fresh and dry mass of the aerial part and production components (number of pods per plant; number of grains; number of grains per pod; mass of 100 grains; grain yield. The presence of B. aryabhattai favored soybean in lower water deficit (-15 and -25 kPa), increasing productivity. At -45 kPa, the influence was limited due to extreme water stress. In the absence of B. aryabhattai, the best results were also observed under lower water deficit (- 15 kPa).