Effect of Bacillus aryabhattai inoculation associated with other species of the Bacillus spp. genus on Urochloa ruziziensis under water deficit

• Grant number: 25/04851-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2025
• End date: November 30, 2025
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: Guilhermo Francklin de Souza Congio
• Grantee: Victor Gennaro Mondelli
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Tropical forage grasses are widely used in Brazil and represent the largest area, planted or native, dedicated to the country's agribusiness. The prominence of these species is due not only to cattle production but also to agricultural production in integrated systems and no-tillage. The species Urochloa ruziziensis is one of the most used in consortium with second-crop corn for soil cover and structuring and subsequent grazing by animals. However, its development is hampered by the water seasonality of the cultivation regions. Plant growth-promoting bacteria (PGPB) are recognized for acting in various functions in association with plants, such as protection against pathogens, production of phytohormones, and aid in resistance to abiotic stresses. However, studies developed on the use of PGPB in tropical pastures are relatively scarce. This project aims to evaluate doses of the mixture among the PGPB Bacillus aryabhattai (75% of the mixture in colony-forming units), B. subtilis (15%), and B. amyloliquefaciens (15%), via seed treatment and foliar spraying, on the population density of tillers and forage production of U. ruziziensis grass in a greenhouse. The experiment will be conducted at ESALQ/USP, Piracicaba, SP, from January to July 2025. The treatments will correspond to different doses of the mixture among the PGPB, inoculated via seed treatment (Exp. 1) and via foliar spraying (Exp. 2) in U. ruziziensis, cultivated in a greenhouse. The experimental design used will be completely randomized, with five repetitions (pots). The data will be analyzed using RStudio® software, with the use of the ANOVA variance analysis model