The effect of sugarcane straw deposition on soil microbial community associated with phosphorus solubilization

• Grant number: 17/09852-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): November 01, 2017
• Effective date (End): October 31, 2018
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Fernando Dini Andreote
• Grantee: Julia Capozzi Franke
• Home Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Sugarcane is currently the most important agricultural crop in the State of São Paulo and plays a prominent role among the main crops in Brazil. Within the management of this crop, the maintenance of straw on the soil surface results in improvement of the physical and chemical attributes, contributing to the increase of the carbon stock, biological activity and water storage, conferring a nutritional improvement of the soil. This nutritional improvement is associated to the fact that the straw incorporation stimulates the microbial activity of the soil that assists in the availability of nutrients to the plants, among them phosphorus. Brazilian soils present a greater tendency to the predominance of inorganic phosphorus forms strongly linked to mineral fraction and physically and chemically stabilized organic forms. Several microbial groups have the capacity to mineralize organic phosphates and to solubilize inorganic phosphates, allowing their absorption by plants. The objective of this proposal is to evaluate the effects of the disposal of different amounts of sugarcane straw (0, 5, 10 and 15 mg ha-1) in soils with different textures (clayey and sandy) on the diversity and the functioning of the microbial community associated with phosphorus solubilization. The evaluations of the microbial community will be carried out using independent cultivation methodologies (eg, qPCR and DGGE), and the results obtained are correlated with the environmental data (soil physical and chemical attributes). In this way, the proposal aims to obtain a better understanding of the microorganisms responsible for the release of phosphorus from the degradation of sugarcane straw. It is hoped that the results can aggregate information for decisions in the sugarcane production system, providing an option for a more efficient and sustainable management of the crop. (AU)