CONTROL OF SOUTHERN ARMYWORM AND BEET ARMYWORM ON STAKED TOMATO, 2001

Southern armyworm is the principal early-season pest of fall tomatoes in southwest Florida, capable of destroying a crop if left uncontrolled. This trial examined a wide range of insecticide types alone and in combination or rotation to provide growers additional options for controlling these pests. Greenhouse-raised seedlings were planted 11 Sep at 18-inch spacing on 6 raised beds 490 ft long on 6-ft centers, each covered with whiteface polyethylene film. Plants were irrigated and fertilized using Netafim drip tape with 12-inch spacing between emitters. The center bed of each set of three beds was left untreated to serve as a source of pest inoculum. The treated beds were divided into plots 35 ft long to which 14 treatments were assigned in a completely randomized block design with four replications. A precount 19 Oct showed 9 % of 160 plants sampled across the trial had worms present. Treatments were applied in six weekly applications initiated 22 Oct using a high clearance sprayer with two vertical booms operating at 200 psi. Each boom was fitted with three ceramic yellow Albuz hollow cone nozzles for the first four treatments to deliver 66 gpa. An additional nozzle added to each boom for the last two applications raising the output to 88 gpa. The Avaunt and DiPel treatment was a weekly rotation starting with Avaunt. The adjuvant Kinetic was tank mixed with the Proclaim treatments at 0.25% v/v. Number of larvae and damage on four plants per plot were monitored weekly five times starting 26 Oct. Damage was rated as 0 = no damage, 1 = 1% leaflets with damage, 2 = 2 to 5%, 3 = 6-15%, 4 = 16-30% and 5 implies >30%. Vacuum samples to evaluate spiders and parasitic wasps were taken on 26 Oct, 9 and 27 Nov and 10 Dec from Avaunt at 0.65 lb/AI, Lannate and the untreated plots using a modified Homelite leaf blower. All fruit of marketable size from 16 plants per plot was harvested on 3 and 17 Dec. Fruit was classified as marketable or not and sized on a commercial grading table.