Location: Crop Genetics Research
Project Number: 6066-22000-094-002-A
Project Type: Cooperative Agreement
Start Date: Sep 20, 2025
End Date: Sep 19, 2027
Objective:
1. Determine the efficacy of different production practices on mitigating the effects of the pest threats, especially nematodes.
2. Monitor for emerging cotton pests and plant diseases and develop methods to evaluate cotton plant diseases, especially early season threats, and use them to identify cotton lines with genetic resistance to these diseases.
3. Characterize plant growth and development responses to exposure to pests especially reniform nematodes or those pests prevalent early in the growing season.
Approach:
Trials will be conducted in growth chambers in pots infested with reniform nematodes. The entries will include two commercially available reniform nematode-resistant cotton cultivars and a reniform nematode-resistant breeding line as well as including reniform nematode-susceptible lines as checks. Two treatment strategies will include both “low” and “high” reniform nematode infestation concentrations to determine the resilience of the resistance / tolerance under varying levels of reniform nematode pressure.
To identify the early season pests and plant diseases that should be targeted for diagnostic screening tests of cotton lines and cultivars, a statewide monitoring will be conducted throughout the 2025 growing season and repeated in 2026 and 2027. The information will be collected from the Mississippi State University collaborators and their colleagues to provide the best possible information.
Based on the monitoring results, diseases and the causal organisms involved will be prioritized and screening protocols implemented for elite cotton breeding lines and commercial cultivars. Early season diseases are the primary focus of the research as these have already been identified as perennial problems with few economically viable mitigation solutions. For example, seedling diseases, including those caused by Rhizoctonia solani have been reported to cause estimated losses of 140,745 bales (67 million lbs) annually. Currently there are no commercially available resistant commercial cultivars for any of the seedling disease causing organisms consisting of the true fungi (e.g., Fusarium, Rhizoctonia, Thielaviopsis). For the purposes of this screening, a recently published greenhouse protocol will be adopted for the growth chamber to evaluate cotton lines as to whether or not they have resistance / tolerance to the complex of organisms that cause seedling diseases which includes Rhizoctonia solani and some of the additional seedling disease-causing organisms.
Additional cotton diseases already known to cause significant economic loss for farmers, such as bacterial blight, would be screened as well under this project since bacterial blight remains a major problem for profitable cotton production across the cotton production system. As the project moves forward, monitoring, including the use of plant disease surveys, will remain a critical component of the overall approach and development since this will provide sources of isolates for screening protocols. Should additional, “new” pest threats emerge, the project will respond proactively to address those threats.