Diamond insecticide, registered last season for the control of plant bug and stink bug nymphs and other insect pests in cotton, is now approved for control of cotton fleahopper nymphs at a rate of 6 to 9 ounces per acre.

Replicated trials conducted by Roy Parker, Extension entomologist at the Texas Agricultural Experiment Station at Corpus Christi, show that sequential applications of Diamond at 6 ounces per acre provided 100 percent control of a low population of cotton fleahopper nymphs at three days and six days after the second treatment.

Applied when insect pests are in the larvae/nymph stage, Diamond controls insects by interfering with chitin development. It has been proven effective in preventing juvenile tarnished plant bugs, clouded plant bugs, stink bugs, armyworms, loopers, budworms, bollworms, cotton leaf perforators and salt marsh caterpillars from reaching the next growth stage.

Diamond controls immature stages of insect pests, such as plant bugs and stink bugs both through contact activity and ingestion, and is shown to reduce feeding damage on bolls and blooms. It may be applied alone for control of juvenile insects, in a tank-mix combination with conventional pyrethroid or organophosphate insecticides, or in rotation with neonicotinoid insecticides for control of mixed populations of juvenile and adult insect pests.

USDA-ARS trials conducted last season at Stoneville, Miss., showed that Diamond reduced tarnished plant bug nymphs to fewer than one nymph per 12 feet of row, compared to populations of 10 or more nymphs per 12 feet of row in the untreated check.

Auburn University trials have shown that a tank-mix application of 6 ounces of Diamond and 4 ounces of Bidrin for control of tarnished plant bugs resulted in zero bloom damage, and just 5 percent boll damage, at 20 days after treatment (DAT). A 9-ounce application of Diamond alone held bloom and boll damage to 3 percent at 20 DAT. That compared to 25 percent bloom damage and 35 percent boll damage for the plot treated with an 8-ounce application of Bidrin alone, and 17 percent bloom damage and 12 percent boll damage for the plot treated with a 2-ounce application of Centric, at 20 DAT.

Diamond has been granted "OP Replacement" status by the EPA, with a worker re-entry interval of just 12 hours.

For more information. contact a crop protection supplier or Extension agent.