Modeling Asian Soybean Rust and Future Implications for the Sustainability of Brazilian Soybean

• Grant number: 24/22984-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: July 01, 2025
• End date: February 28, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Agricultural Meteorology
• Principal Investigator: Fabio Ricardo Marin
• Grantee: Gustavo de Angelo Luca
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 21/10573-4 - Center for Carbon Research in Tropical Agriculture (CCARBON), AP.CEPID

Abstract

Soybean (Glycine max L. Merr) is the world's primary source of plant-based protein and plays a fundamental role in global food security, being essential for the production of animal-based foods. Brazil, the world's largest producer, faces significant challenges in maintaining productivity due to production-reducing factors such as pests, diseases, and weeds. Among these, Asian soybean rust (Phakopsora pachyrhizi) stands out as one of the most critical, capable of causing substantial yield losses under uncontrolled conditions and representing one of the highest phytosanitary costs in soybean cultivation.This study aims to assess the impacts of climate change on the severity of Asian soybean rust and its implications for phytosanitary management, focusing on the energy and environmental sustainability of soybean production in Brazil. Using an epidemiological model integrated with DSSAT/CROPGRO-Soybean and validated with field data, the research seeks to simulate disease severity under future scenarios, considering three time periods (2020-2039, 2040-2069, and 2070-2100) and different socioeconomic pathways (SSP1-RCP2.6, SSP2-RCP4.5, and SSP3-RCP7.0).Simulations will be conducted in three major soybean-producing regions (South, Central, and North), analyzing productivity with and without the disease's impact and estimating the number of fungicide applications required for control under future conditions. Additionally, direct and indirect energy flows associated with input use and agricultural operations will be quantified. The analysis of the energy balance, integrated with climatic and phytosanitary impacts, will enable the calculation of indicators such as energy efficiency, net energy balance, and energy return on investment.The expected outcomes include an evaluation of Asian soybean rust severity under high-emission scenarios, the frequency of fungicide applications, and the energy and environmental impact on soybean production. Moreover, integrated management strategies will be proposed to reduce the economic costs and ecological damages associated with intensive use of agrochemicals. By doing so, the research seeks to contribute to the development of public policies and more sustainable agricultural strategies, reinforcing the importance of adaptation to climate change to ensure soybean productivity and global food security. (AU)