The cotton jassid, Amrasca biguttula, (a.k.a. two spotted cotton leafhopper) has been found in multiple locations in southern Georgia and in South Carolina. This small green leafhopper has a wide host range including cotton and a variety of vegetables. The only damaging populations reported to date have been on okra, with 100+ per leaf. They cause what is generally referred to as hopperburn: yellowing, reddening then browning of leaves followed by wilting and curling. In okra they were found both on the top and bottom of leaves, but primarily along the main leaf veins on the bottom. The cotton jassid adults are readily separated from other small green leafhoppers by distinct dark spots near the wing tips. In vegetables, the greatest potential for damage is reported for okra and eggplant.
Dr. Roberts and I have done some quick bioassays with adults and the results are “inconclusive”. Dr. Roberts got reasonably good mortality with two cotton products we can not use in vegetables. He also got 75-80 % mortality with Assail and Actara. In my bioassay, Venom gave about 60% control and everything else performed poorly (including other neonics, pyrethroids, Group 28s, Lannate, Torac). It is worth noting that this pest is on IRAC’s (Insecticide Resistance Action Committee) radar with reported resistance to OPs, carbamates, pyrethroids and neonicotinoids.
