POTENTIAL OF PHOSPHORUS SOLUBILIZATION BY Bacillus velezensis UFV 3918 UNDER THE USE OF MINERAL PHOSPHATE AND FILTER CAKE IN SUGARCANE IN CONTRASTING PRODUCTION ENVIRONMENTS

• Grant number: 23/12102-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: June 01, 2024
• End date: February 28, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Marcelo de Almeida Silva
• Grantee: Hariane Luiz Santos
• Host Institution: Faculdade de Ciências Agronômicas (FCA). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Phosphorus (P) plays a crucial role in several plant metabolic processes. However, among the macronutrients, P has the lowest use efficiency in agricultural production due to the high retention rate of its ions. As a result, this is one of the nutrients that most limits the yield and longevity of sugarcane fields, which implies the intensive use of synthetic phosphate fertilizers to increase yield. In this context, the possibility arises to investigate the bacteria inoculation associated with less soluble phosphate fertilizers and filter cake. This approach can be a promising alternative since some bacterial strains can hydrolyze insoluble organic and inorganic P compounds, transforming them into soluble forms that plants can assimilate. In addition, these microorganisms produce phytohormones responsible for stimulating plant growth, providing an ecologically correct and economically viable strategy to overcome P fixation and its subsequent plant uptake. Starting from the assumption that the bacteria can allow the reduction of P doses without compromising the sugarcane productivity, the present research aimed to analyze the morphological, physiological, biochemical, nutritional, and yield responses of sugarcane, as well as to evaluate the chemical and microbiological responses of the soil, resulting from the inoculation of Bacillus velezensis UFV 3918. In two contrasting production environments, inoculation will be studied alone and in combination with Bayóvar natural reactive phosphate (NRP) and filter cake (FC). The experiments will be carried out during two one-year cycles - October 2023 to October 2024 (plant cane) and November 2024 to November 2025 (ratoon cane), with an area located in Barra Bonita-SP, in a production environment A-B, and another in Lençóis Paulista-SP, in production environment D-E. A randomized block design will be adopted, in a 2×5 factorial scheme, consisting of the presence or absence of B. velezensis UFV 3918 and a combination of doses of NRP and FC [absolute control (without NRP and FC); commercial control - recommended dose (RD) of NRP + FC; 75% NRP + 25% FC of RD; 50% NRP + 50% FC of RD; 25% NRP + 75% FC of RD], with four replicates. Data will be submitted to normality and homoscedasticity tests and, after meeting the assumptions, will be submitted to analysis of variance by F test, with subsequent comparison of means by Tukey's test (pd0.05). Principal component analysis will be applied using the nonlinear iterative partial least squares algorithm, and Pearson's linear correlation will be analyzed (p<0.01).