Wireworm Control on Potato, 1991

Abstract

Abstract Certified LaRouge' seed pieces were planted on 19 Nov 1990 in a 0.4 acre area with Perrine marl soil and spaced 4 inches apart in rows that were 3 ft apart. Nine treatments were arranged in a randomized complete block design with 4 replications. Treatment plots consisted of 4 rows 12.2 m long. Plants were fertilized with 1700 lb/acre of granular fertilizer (6:12:10) at planting. Monitor was applied (1.0 qt [AI]/acre) on two dates and Pounce was applied (6 oz [AI]/acre) on four dates to control green peach aphid, Myzus persicae (Sulzer), and Thrips palmi Karny. In addition, Trigard was applied (1.2 lb [AI]/acre) on 17 Jan to control leafminers, Liriomyza sativae Blanchard and L. trifolii (Burgess). Topsin was applied (1 lb [AI]/acre) on 17 and 21 Jan to control plant pathogenic fungi. The insecticides tested were: EXP 60166A, Thimet, PCC300 (10% [AI] ethoprop and 10% [AI] phorate), and PCC 307 (8% [AI] fonofos and 12% [AI] phorate). Treatments evaluated were: EXP 60166A (0.1, 0.2, and 0.3 lb [AI]/acre), Thimet (3.6 lb [AI]/acre), PCC 300 (2.0 and 3.0 lb [AI]/acre), PCC 307 (1.9 and 2.5 lb [AI]/acre), and a nontreated check. Insecticides were manually sprinkled over the seed pieces in the furrow and covered with soil four days after planting. Vines were killed on 19 Feb 1991 with Paraquat Plus (1 qt/acre; 29.1% [AI]). Two 20 ft sections of row per treatment plot were harvested on 7 Apr 1991. Tubers were washed, graded for wireworm injury (tubers with ≤2 holes per tuber with a combined depth ≤3/4 inch) or damage (tubers with at least 1 to 2 holes per tuber with a combined depth >3/4 inch or >2 holes per tuber), cracking, sunburn, disease, etc., and fresh weight. Data for injury, damage, sunburn, and cracking are presented as a percentage of total fresh weight per harvested section of row.