Quantification of citric acid in the rhizosphere of Glycine max under water deficit in contrasting microbiomes from Caatinga and Mata Atlântica soils.

• Grant number: 24/21118-4
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: April 01, 2025
• End date: July 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Fernando Dini Andreote
• Grantee: Gabriel Moreno Castilho
• Supervisor: Antonio Marcos Miranda Silva
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Institution abroad: University of Southern Denmark (SDU), Denmark
• Associated to the scholarship: 24/05748-8 - Analysis of metabolites produced in Glycine max in response to water stress under different microbiomes of dryland soils, BP.IC

Abstract

Drylands cover approximately 45.4% of the Earth's surface, housing around 2.2 billion people. Due to the extreme climatic conditions, the microbiota in these areas has developed a unique biodiversity and resilience to harsh environments. However, desertification poses a significant threat to this diversity and agricultural productivity. Among the various stresses present in these regions, water stress is particularly pronounced, compelling plants to utilize exudates to interact with microbiota, potentially allocating up to 40% of their photosynthates for this purpose. Among the compounds found in these exudates, citric acid plays a crucial role in plant microorganism communication under stress conditions and is integral to plant physiology in drought scenarios. Citric acid will be extracted from the rhizosphere soil using a Diffusive Gradient in Thin Films (DGT) method and subsequently quantified through colorimetry or, if concentrations are too low, via liquid chromatography. Additionally, Dissolved Organic Carbon (DOC) and Water-Extractable Phosphorus (WEP) will be quantified to estimate microbial activity and its influence on soil under water deficit conditions. The data will be analyzed for homogeneity and normality, followed by analysis of variance (ANOVA) and Tukey's test (p < 0.05) for mean comparisons, with non-parametric analyses employed as necessary. The expectation is that the quantification of citric acid, DOC, and WEP will provide deeper insights into the influence of microbiomes in plants and their impact on soil under drought conditions, promoting more sustainable agricultural practices that enhance resilience to environmental stress.