Beet Curly Top Virus Report

Beet leafhopper counts were still very low throughout November. Non-target leafhoppers were more abundant.
Beet leafhopper samples were challenging to obtain because BLH were widespread and difficult to find. Fall host plants were declining in suitability for the BLH and winter host plants were just beginning to germinate.
Field conditions for Fresno, Kern, and Kings Counties were very similar. Fall BLH host plants along roadsides and fallow fields were showing signs of advanced stress. The majority of the fall host vegetation was not viable for BLH, therefore, there was very little observable BLH activity during surveys in November. Average BLH counts were 0-1 adult per sweep.
After a rain event at the end of October, filaree and winter grasses began to emerge in some locations on the hillsides. Filaree remained small and in the early stages of germination. Due to very little rainfall over the course of November, the majority of the filaree had begun to stress and die off. The rainfall that occurred toward the end of November, helped to revive some of them. The winter grasses have continued to develop.
There were three (3) host plant samples collected in Fresno County and submitted for virus analysis. All three (3) samples were negative for curly top virus.
There were three (3) BLH samples collected in Fresno County and submitted for virus analysis. Only one (1) was positive for curly top virus.

Personnel conducted beet leafhopper and host plant vegetation surveys in the agricultural areas of the desert the week of November 14th. Areas surveyed included Blythe, Holtville, El Centro, and Calipatria. BLH activity was low, with an average of 1-5 adult BLH per 10 sweeps. Non-target leafhoppers were more abundant.
There were ten (10) host plant samples collected and sent for virus analysis. All ten (10) were negative for curly top virus.
There were three (3) BLH samples collected and sent for virus analysis. All three (3) were negative for curly top virus.
Agricultural roadways and roadsides were well maintained and clean, with very limited host vegetation.

BLH counts remained very low with an average of less than 1 adult BLH per sweep. Non-target leafhoppers were more abundant during sweep surveys.
Personnel will continue to monitor BLH populations and collect both host plant and BLH samples for virus analysis.

BLH counts remained very low with an average of 0-1 adult BLH per sweep. Non-target leafhoppers were more abundant during sweep surveys.
One (1) BLH sample was collected and sent for virus analysis. It was negative for curly top virus.
One (1) plant sample was collected and sent for virus analysis. It was determined to be Mexican sprangletop, a weed the Program was not familiar with. The BLH were swept from this weed but none were observed on typical BLH host plants at the time of survey. It was negative for curly top virus.
Personnel will continue to monitor BLH populations and collect both host plant and BLH samples for virus analysis.