Insecticidal Activity of Products Applied for Control of Tobacco Cyst Nematodes, 1988

Experimental plots consisting of 1 border row and 1 40-ft test row (24 plants) were established on 4-ft centers in a field infested with a tobacco cyst nematode, Globodera tabacum subsp. solanacearum (Miller and Gray) Stone, at the Southern Piedmont Agricultural Experiment Station, Blackstone, Va. The soil was an Appling sandy loam (pH 6.1, 2-7% slope, 1.2% organic matter). Plots were arranged in a randomized complete block design with 4 replicates. Liquid nematocides were applied on 29 Apr (air temperature 64°F, soil temperature 55°F, 25% soil moisture) using a tractor-mounted sprayer equipped with 8003LP nozzles spaced 20 inches apart. Sprayed treatments were applied at 25 psi to attain a delivery volume of 32 gal/acre. Liquid nematocides were incorporated by disking immediately after treatment. Temik 15 G treatments were applied using a Gandy apparatus mounted to a pushcart. Preplanting Temik treatments were applied 2 May and incorported by bedding the soil immediately after treatment. Temik sidedress treatments were applied on 19 May and incorporated immediately by cultivation of the bed. ‘Coker 319’ tobacco was transplanted into the field on 3 May. Supplemental irrigation was applied 69 and 78 d after transplanting. Fertilizer and other cultural and pest control practices conformed to recommendations of the Virginia Cooperative Extension Service. Five plants/plot were examined 24 d after transplanting for number of flea beetles and number of flea beetle holes on the most damaged leaf.