Increasing Outbreaks and Impact of Iris yellow spot virus in Bulb and Seed Onion Crops in the Imperial and Antelope Valleys of California

Abstract

Outbreaks of IYSV were first observed in May 2003 in two Imperial County onion seed fields. In August, 2005, symptomatic onion plants were widespread in four fields in the Antelope Valley, Los Angeles County, CA. IYSV infection was confirmed by ELISA and RT-PCR. This was the first known recording of IYSV in Antelope Valley. Increasing incidence and impact of IYSV in a major onion-growing area highlights the need for research into developing managing options for this important disease of onion. Accepted for publication 22 January 2007. Published 8 May 2007.