Impact of fungal plant pathogens on soil carbon sequestration in cotton

Overview

This research program investigates how soil-borne fungal pathogens affect carbon sequestration in agricultural soils, with a focus on cotton production in the semi-arid Southern High Plains of Texas. While foliar pathogens are known to increase plant evapotranspiration and heat stress sensitivity, the role of soil-borne pathogens in limiting carbon storage remains poorly understood. The project addresses this gap by examining how pathogens such as Pythium, Rhizoctonia, and Fusarium compete with beneficial soil organisms and trigger physiological changes in plants that may reduce biomass production and soil carbon inputs. The findings will support selection of pathogen-resistant cotton varieties and management practices that preserve or enhance carbon sequestration, offering value to growers, agronomists, and stakeholders interested in climate-smart agriculture and soil health.

Technical specifications

Research approach:

• Quantification of pathogen population densities using reverse-transcription quantitative PCR (RT-Q-PCR) to measure infection levels
• Measurement and capture of CO2 to assess carbon sequestration under varying pathogen pressures
• Evaluation of multiple cotton varieties with differing levels of resistance to soil-borne pathogens
• A split-split plot experimental design that incorporates pathogen type, variety, and management variables
• Field trials and greenhouse studies conducted in the semi-arid Southern High Plains of Texas, where abiotic stress factors add real-world complexity
• Longitudinal CO2 sampling during the growing season to correlate carbon sequestration with disease severity and pathogen pressure

Target pathogens and crop:

• Pythium, Rhizoctonia, and Fusarium (soil-borne fungal pathogens)
• Cotton, including varieties with varying genetic resistance profiles

Technology readiness level

This is an early-stage academic research initiative at the hypothesis-validation phase. The project will begin with initial field quantification to establish baseline pathogen levels and soil carbon dynamics, then track changes across the growing season. Validation will compare carbon sequestration outcomes between cotton varieties under different pathogen pressures. The research builds on prior knowledge that disease can be partially managed through resistant variety selection, while also acknowledging that this tool is not always fully effective. Future work will expand understanding of pathogen-driven limitations on soil carbon storage under the combined stresses typical of semi-arid production environments.