Project Overview

Reports

Commodities

• Agronomic: cotton

Target Pests

Practices

• Pest Management: cultivation, cultural control, disease vectors, economic threshold, genetic resistance, habitat modification, host resistance, mechanical control, monitoring/scouting, sanitation, weather monitoring

• Crop Production: cropping systems, varieties and cultivars

• Natural Resources/Environment: indicators

Cotton leafroll dwarf disease (CLRDD), caused by the Cotton leafroll dwarf virus (CLRDV), was first reported in the United States during 2017 in Alabama. The virus is transmitted by the cotton aphid, which is ubiquitous in the US cotton belt. The virus quickly spread to other southern states within two years, and to date has been confirmed from South Carolina to Texas. Yield losses from CLRDV in South America, where the virus has occurred for many years, are reported to be up to 80% in susceptible varieties. Significant yield losses have been observed from fields in AL, MS and GA during the 2018-2019 growing season. It is currently unknown when CLRDV infection occurs, the length of latency periods, disease progression and symptom development, the effect of environmental factors on disease, and yield effects.

The purpose of this proposal is to form a collaboration among cotton producing states across the cotton belt to establish a national CLRDV sentinel plot monitoring program and fund meetings critical for information exchange. Sentinel plots will be established in each state representing the working group and will be designed to generate basic information about CLRDV spread and incidence across the cotton belt, virus-variety-environment interactions underlying symptomology and disease progression, aphid seasonal dynamics, and yield loss. Collaborators from each state will monitor the sentinel plots throughout the season and collect data. Samples will be collected from each plot at the end of the season to confirm the presence of CLRDV in each plot. The funds will be used to support diagnostic efforts for the sentinel plot program and hold a formal working group meeting to share observations and data obtained from the sentinel plot program. Data and information exchange will help identify local and regional research priorities, identify future funding sources, begin to develop management strategies for the disease, and coordinate extension messaging. Sentinel plot establishment, maintenance and monitoring will be funded through other sources (Cotton Inc. and state cotton commissions).

Specific objectives of this proposal include: 1) Form a collaboration (working group) among states in the US cotton belt. 2) Coordinate sentinel plot research trials among members of the working group to monitor for infection, vector activity, symptom development, disease progression, genetic susceptibility of cotton varieties and yield impacts. 3) Analyze samples from all sentinel plots for the presence of CLRDV. 4) Develop management recommendations that reduce yield loss caused by CLRDD and minimize impacts on other organisms and the environment. 5) Identify research priorities for future research on CLRDD.

Knowledge and key findings will be presented to extension agents, growers, crop consultants, and industry partners through presentations at Extension, commodity group and crop consultant association meetings across the south. Research results will be shared with the broader scientific community and industry partners through presentations at regional and national scientific meetings and refereed, open-access scientific journals.

Confirmed participation includes Auburn University, University of Georgia, Clemson University, University of Florida, North Carolina State University, Virginia Tech, Mississippi State University, University of Arkansas, University of Tennessee, Louisiana State University, and Texas A&M University.