OSIB: Co-evolutionary dynamics of pathogen virulence and host resistance: lessons from Fusarium oxysporum-infested cotton fields

As the world population grows, agriculture faces challenges in increasing the yield and quality of crops. One of the biggest obstacles is crop diseases, which can cause significant damage to important crops and limit production. Fusarium oxysporum is a fungal pathogen that is known to cause severe damage to many crops, including cotton.

Recently, there has been an outbreak of cotton Fusarium wilt caused by F. oxysporum f. sp. vasinfectum (Fov) in some southern U.S. states. This project aims to better understand the evolution and pathogenicity of F. oxysporum and to identify resistance genes that could help protect crops. The project will also provide opportunities for training and education in plant genomics and molecular biology for undergraduate and graduate students, as well as outreach opportunities for underrepresented minorities and African scientists.

By using cutting-edge technologies, this project will advance our understanding of F. oxysporum and its interactions with hosts, which could ultimately lead to more effective disease management strategies and increased crop production.

Over several years, the team has collected data on the pathogen characteristics and germplasm screens of a naturally infected cotton field in Texas. Based on this data, they have developed a hypothesis about the evolution and pathogenicity of F. oxysporum and gained molecular insights into the fungus-host interactions. They have also created platforms for transient and stable assays to study the loss and gain of function in cotton.

The team aims to determine the genetic diversity, evolution, and pathogenicity of Fov and other F. oxysporum species and understand cotton's resistance mechanisms to Fusarium wilt through association genomics. The research will take a systems approach to understanding the co-evolutionary dynamics of pathogen virulence and host resistance in the complex genome of both the fungus and cotton.

F. oxysporum species complex (FOSC) is a group of isolates with different host specificities, which are defined as formae speciales. FOSC has complex genome structures with core chromosomes and accessory chromosomes that may be associated with virulence and host specificity. The proposed research will explore the evolutionary dynamics of accessory chromosomes and their role in virulence and host specificity.

The project will provide insights into Fov-cotton interactions and a broader understanding of F. oxysporum-host interactions.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.