Impact of Insecticides Alone and in Rotation on Tomato Pinworm, Leafminer and Beneficial Arthro-Pods on Staked Tomato, 1997

Abstract

Abstract Greenhouse-raised tomato seedings were planted 18 inches apart on 4 sets of 3 subirrigated beds, 32 inches wide and 240 ft long, on 12 Mar. Beds were fumigated with a 67/33% mixture of methyl bromide and chloropicrin at a rate of 220 lb acre, fertilized, and covered with black polyethylene film mulch. The middle ‘inoculum’ row of each 3-bed set was left untreated. The remaining 2 beds in each set were divided into 8 plots about 30 ft long to accommodate 14 treatments and untreated check in a RCB design replicated 4 times. Plants were sprayed weekly with a combination of Maneb 80 WP at 1 lb/acre plus Kocide 101 at 3 lb/acre for disease control. Two wing-type sticky traps, baited with TPW pheromone (Scentry) lures placed in the field to monitor the pinworm population, showed peaks on four dates 3,4, 25 Apr and 2 May when the daily trap catch was 21, 26, 30, and 32, respectively. All other dates had a daily trap average of less than 10. Pre-treatment means of 20.5 LM and 3.4 PW mines/plant were recorded on 11 Apr. Seven weekly treatments were applied from 14 Apr through 30 May using a high-clearance sprayer with 2 booms fitted with “yellow” Albuz® hollow-cone nozzles operating at a pressure of 200 psi. The first 2 applications used 4 nozzles, 2 per boom, to deliver 42 gpa and the last five used 6 nozzles for 65 gpa. Three treatments con-sisted of SpinTor applied for 2 weeks followed by an application of Trigard, Agri-Mek, or Mattch. RH-2485 and Confirm were tank mixed with the adjuvant Latron CS-7 (0.12% v/v). Five weekly counts were made of dead/empty mines and live larvae of the LM and PW from one side of two plants, 4 samples per plot. Weekly vacuum samples of 4 sees from one side of 6 plants were taken beginning 17 Apr using a modified leaf blower. Catch was identified as beneficial (primarily spiders, hymenoptera exclusive of ants and predaceous hemiptera), pests and incidental (mostly flies). Fruit was harvested 3 Jun from 6 plants per plot and the marketable fruit graded on a commercial table with weights and numbers recorded. Unmarketable fruit was separated into categories of infestation with TPW, other insects and disease. Crop value was estimated based on $5,6,7,9 market per box of small, medium, large, and extra large fruit, respectively.