Project Overview

Reports

Commodities

• Agronomic: cotton

Target Pests

• Target Pests: other

Practices

• Pest Management: monitoring/scouting

Problem:

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 three years, and to date has been confirmed from Virginia 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. Yield losses of up to 25% have been observed from fields in AL, MS and GA between the 2018-2020 growing seasons. 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 impacts.

Investigative approach:

Observations from the 2020 sentinel plot program were used to modify the sentinel plot program design and procedures for 2021. 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 60 and 120 DAE to confirm the presence of CLRDV in each plot at different points during the season. The funds will be used to support diagnostic efforts for the sentinel plot program and to coordinate data analysis 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). 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.

Anticipated Impact:

Continuation of this current IPM funded project will allow for continued farmer outreach and education on effective management strategies to reduce economic yield losses due to CLRDV and sustain the viability of cotton production in the U.S. 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.

Project Objectives:

The purpose of this proposal is to facilitate coordination and collaboration among cotton producing states across the cotton belt to continue the national 2020 CLDRV sentinel plot monitoring program for 2021. Specific objectives of this proposal include: 1) Continue to support and encourage collaboration of the 2020 sentinel plot working group among states in the US cotton belt for 2021, 2) Coordinate sentinel plot research trials among members of the sentinel plot working group to monitor for infection, vector activity, symptom development, disease progression, genetic susceptibility of cotton varieties and yield impacts, 3) Exchange and analyze data from all sentinel plots for the presence of CLRDV, 4) Develop management recommendations that reduce yield loss caused by CLRDD and minimize impacts on non-target organisms and the environment, and 5) Identify priorities for future research on CLRDD.