Population dynamics of Circulifer tenellus in southern New Mexico over a seven year period

The beet leafhopper, Circulifer tenellus (Baker), vectors curly top virus, which presents a disease threat to chile grown in New Mexico. While the disease has been recognized in the state since the 1920’s, the impact of the disease varies yearly. To help chile growers predict disease incidence, a beet leafhopper survey was established. Adult beet leafhopper populations were assessed over a 7 year period, 2001-2007 in southern New Mexico using sticky traps placed at the margins of 10 chile fields. Traps were changed every two weeks and numbers of beet leafhoppers were recorded. In addition, weather monitoring stations were placed into four of the fields which monitored temperature, rainfall, humidity, solar radiation, and wind speed and direction. Leafhopper populations fluctuated during the survey with the highest numbers of leafhoppers in 2001 and the lowest in 2006 and 2007. Adult leafhopper numbers increased each year in mid-April to mid May and decreased each year to a minimal levels in late October to early November. Leafhopper numbers were correlated with seasonal rainfall accumulation. The arrival date of the leafhoppers appears to be a combined effect of rainfall and accumulated degree days.