European Corn Borer Control in Snap Beans, 1985

Abstract

Abstract Snap beans were planted at Bancroft, WI on 3 Jun '85 in 3 blocks 10 rows × 240 ft. Each block consisted of 19 treatments and 2 untreated checks each 10 rows × 10 ft. European corn borer (ECB) eggs (ca. 350 eggs/plot) were pinned to the center 20 plants at 28, 25, 18 and 14 days before harvest (dbh) (pre-bud, bud, 10% bloom, and full bloom, respectively) in individual rows for each egg placement date. Insecticide treatments were applied 18 dbh (full bloom/no pods) with a 10 ft boom (20 gpa, 2.5 mph, 25 psi, 8002 Tee Jet tips on 20 in centers) perpendicular to the rows. At harvest 20 plants from each egg infestation date in each insecticide treatment were evaluated for the number of stems and/or pods damaged and the number of ECB in the stem or pods. Larvae were saved for instar determination, beans per plant were counted, and the sieve size of the beans was determined to gauge maturity. The design allowed the evaluation of the influence of infestation date and crop development of insecticide effectiveness. Damaged pods could only result from ECB moving from the stems to the pods after the insecticide treatment.