Managing the primary vector of cotton leafroll dwarf virus does not reduce final virus incidence in cotton

Aphis gossypii Glover is the primary vector for Cotton leafroll dwarf virus (CLRDV), the first reported virus to cause yield loss of cotton, Gossypium hirsutum L., in the southeast U.S. No research has been conducted to assess management strategies of the emerging virus in the U.S. The goal of this research was to quantify the impact of two planting dates and four insecticide spray regimes for reducing aphid populations and final CLRDV incidence in small plot replicated trials conducted in south Alabama and Georgia in 2019. Overall, planting date and insecticide treatment reduced aphid populations, but aphids were present in all experimental plots throughout the study and reached 100% infestation. Planting date and insecticide treatments did not significantly reduce final CLRDV incidence. Final CLRDV incidence ranged from 60-100% and 90-100% of the plants tested within each plot in AL and GA, respectively. This research demonstrated that insecticide treatment and planting date adjustment were not effective in reducing final CLRDV incidence in these trials.