Resistance management of the twospotted spider mite Tetranychus urticae (Acari: Tetranychidae) in North Carolina tomatoes

Recently the twospotted spider mite, Tetranychus urticae, has become a consistent pest of tomatoes in central and western North Carolina. Currently there is no economic threshold or sampling procedure for the twospotted spider mite in staked tomatoes, yet growers rely on chemicals for the control of these mites. Economic thresholds of 0, 1, 8, 17, 25, and 50 mites per leaflet were evaluated by performing an economic analysis on the fruit yields from both early and late planted tomatoes. A sequential sampling plan was developed by using mite densities from staked tomato fields representing different planting times and pesticide regimes in both central and western North Carolina.