WDC007: Iris yellow spot virus (IYSV) and Thrips
Statement of Issues and JustificationGoal: Focus resources on Iris yellow spot virus (IYSV) and thrips for a coordinated research program to minimize the devastating effects of these pests on onion and related crops in the U.S. Besides thrips pressure, this disease could potentially impact the eastern and midwestern regions of onion production in the U.S. if the virus spreads into those regions.
Economic Impacts: Onion is an economically important crop in the U.S., generating over $979 million in farm receipts in 2005 with a potential of $6 billion in value-added benefits. Onion production ranges from 150,000 to 175,000 acres annually, with nearly 80% (120,000 acres) in the western region. A significant portion of the U.S. and world supply of onion seed (20%) is also produced in the Pacific Northwest. Projected economic impacts, if the rate of spread and damage by IYSV and thrips continue unchecked in the western U.S., could reach $78 million (10% loss) to $117 million (15% loss in farmgate value), in addition to environmental and economic costs associated with additional pesticide sprays that have limited efficacy ($7.5 to 12.5 million dollars for 3 to 5 additional sprays to 120,000 acres per year).
Background and Proposal: IYSV and thrips were ranked as # 1 & 2 research priorities in the Western Region Pest Management Strategic Plan developed for dry bulb storage onions in the western U.S. during a regional stakeholder meeting held in 2004 in Boise, ID (http://pestdata.ncsu.edu/pmsp/index.cfm). These priorities were endorsed in 2005 by the Pacific Northwest Vegetable Association and the National Allium Research Conference participants. An Onion Thrips and IYSV Focus Group of concerned stakeholders from the western region met in Fort Collins, CO on March 30, 2006, and prioritized the urgent needs for research and outreach for stakeholders.
Stakeholders (producers, processors, agribusiness support personnel) and research scientists from land grant universities in western (Arizona, California, Colorado, Hawaii, Idaho, Nevada, New Mexico, Oregon, Texas, Utah, Washington) and eastern (Georgia, Michigan, New York, Wisconsin) states are concerned about the lack of funds, lack of coordination, and escalating threat from IYSV and thrips to the economic sustainability and supply of quality onion and related crop products in the USA. Therefore, it is proposed that a multi-state research project be established on the management of IYSV and thrips that will encourage collaborative activities between ARS programs and land grant universities with appropriate expertise in onion pest biology and management.
Potential Objectives: " Develop onion germplasm and cultivars with high levels of resistance to Iris yellow spot virus and tolerance to thrips, " Develop ecologically-based onion production systems that consider the interaction of multiple pests and production practices, " Identify economic injury levels for thrips as a pest and when Iris yellow spot virus is a threat, " Identify cultural and biological tactics that can reduce or replace conventional insecticides for thrips management, and " Develop and implement integrated pest management strategies with the onion industry.
Back to Top