Ecology of the beet leafhopper and beet curly top virus in hemp

Hemp (Cannabis sativa L.), is a rapidly growing industry in the United States. Of which, Colorado is one of the biggest hemp growing states. Beet curly top virus (BCTV), which is transmitted by Circulifer tenellus (beet leafhopper), was recently shown to infect hemp plants in Colorado. Since its initial detection, we have confirmed the virus from 12 counties in Colorado, with several fields reporting disease incidence levels above 50%. Life history assays were performed in BCTV viruliferous and non-viruliferous beet leafhopper to understand the impact-if any, the virus has on vector behavior, survival, and fecundity in relation to hemp as an alternative host plant. A survey of beet leafhopper, weed reservoirs and BCTV was performed in hemp in northern and western Colorado fields to understand their abundance and seasonality in Colorado. The results of this research will improve the understanding of the BCTV pest ecology, provide insight on what influences virus movement throughout Colorado and information regarding timing of beet leafhopper movement through hemp fields. Understanding the pest ecology and vector biology of beet leafhopper in association with hemp will facilitate the development of targeted control strategies through integrated pest management and interruption of transmission cycles, in turn reducing yield losses.