Bacillus aryabhattai Improves Agronomic Performance and Water Use Efficiency of Common Bean Under Deficit Irrigation Levels

The common bean (Phaseolus vulgaris L.) is of great food and economic importance in Brazil, but its productivity is highly affected by water deficit due to its superficial root system and short cycle. With the increase in prolonged droughts, irrigation has become a solution, albeit a costly one, for small farmers. In this scenario, bioinputs, such as Bacillus aryabhattai, represent a sustainable and low-cost strategy to improve crop performance under reduced irrigation conditions. The objective of this study was to evaluate the potential of B. aryabhattai to improve the agronomic performance of the common bean under reduced irrigation levels. A greenhouse experiment was conducted in randomized blocks with a 2 × 4 factorial design (presence/absence of B. aryabhattai and four irrigation levels: 40, 60, 80, and 100% of the ETc). Agronomic and productive variables were evaluated. The results showed better performance at 80 and 100% ETc, achieving 16 and 20 g per plant−1. Inoculation increased water use efficiency by 13% and contributed to higher grain yield. It was concluded that rational irrigation management combined with the use of B. aryabhattai improves agronomic performance and water use efficiency under reduced irrigation levels.