Yellow Vein Clearing Virus Spreads in California

Tacy CalliesCalifornia Corner, Diseases

Positive identifications of citrus yellow vein clearing virus (CYVCV) have been found in the Hacienda Heights area of Los Angeles County. The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service confirmed the identifications during the California Department of Food and Agriculture’s (CDFA) routine multi-pest survey.

This is the second area in California where CYVCV has been detected. The first detections were in Tulare County in March 2022.

In response to the additional detections of the virus, CDFA is surveying residential properties within a 1-mile core radius area around the initial find site in Los Angeles County. CDFA seeks to fully determine the extent of the disease’s presence in the area.

CYVCV is an emerging disease of citrus that can lead to significant economic losses to the industry. It can cause serious damage to most citrus species and can dramatically diminish fruit marketability. CYVCV was first discovered in 1988 on lemon and sour orange trees in Pakistan. In 1997, CYVCV symptoms were observed on other lemon cultivars, limes and sour oranges in several regions of India. It has since been detected in Turkey and China.

CYVCV can be spread by vectors as they move from tree to tree feeding on foliage. The vectors include citrus whitefly, green citrus aphid, melon or cotton aphid, and cowpea aphid. All of these vectors are known to be present in California. CYVCV can also be spread through grafting, by the movement of infected propagative materials and rootstocks, and via contaminated tools and equipment.

While there is no treatment for CYVCV, as of now, the best mitigation measures are to control the virus’ vectors and sanitize tools and equipment. To the greatest extent possible, growers are encouraged to urge their field crews to clean and sanitize all their equipment thoroughly in between jobs or when moving between groves.

For questions about CYVCV, call the CDFA Pest Hotline at 800-491-1899 or visit CDFA’s website.

Source: Citrus Pest & Disease Prevention Program