Inoculation of cover crops and maize with phosphate-solubilizing bacteria in a succession system

• Grant number: 24/16473-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2025
• End date: December 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Anderson Prates Coelho
• Grantee: Victor Hugo de Souza
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Understanding how the combination of phosphate-solubilizing bacteria (PSB) and cover crops may optimize resources in a succession system while improving soil quality is essential for more sustainable agriculture. The aim is to determine whether inoculation with PSB and the succession of cover crops and maize will improve (i) development, (ii) nutrition, (iii) yield of these crops, and (iv) the soil physical and biological quality. The experiment will be conducted in Jaboticabal/SP during the 2024/25 season. The experimental design will be a randomized block design with a split-plot scheme (9x2), with four replications. One of the factors under study will be 9 cover crop treatments in the autumn/winter (May): Ukrainian oat, hairy vetch, buckwheat, a mix of these three species, and fallow, which are species more adapted to autumn/winter. The cover crop seeds will be inoculated and non-inoculated with PSB, include 9 treatments. In succession, the AG8701 PRO4 maize hybrid will be grown, both inoculated and non-inoculated, with sowing in August (third-crop season). The commercial product SolubPHOS will be used for inoculation (Bacillus subtilis (CNPMS B2084 (BRM034840)) and Bacillus megaterium (CNPMS B119 (BRM033112)), with a concentration of 4 x 109 viable cells mL-1. The rate will be 250 mL ha-1 for both cover crops and maize. In cover crops, the dry mass left on the soil and P accumulation in straw will be evaluated, while in maize nutritional and physiological variables, growth, yield and P accumulation in grains and straw will be evaluated. After maize harvest, soil samples will be collected to determine soil physical and biological variables. The results obtained are expected to promote greater yield and soil quality in the production system.