Presence of and Damage Caused By Japanese Beetle Adults on Treated Grape Foliage, 1983

Abstract

Abstract Ten treatments were evaluated for repelling and preventing damage by Japanese beetle adults at Wooster, Ohio. Plots consisted of three grape vines, having four replications per treatment in randomized blocks. Vine spacing was 2.7m (9 ft) between rows and 2.4 m (8 ft) within the row. Treatments were applied 7 and 20 July and 4 Aug. as foliar sprays at the rate of 935 liters/ha (100 gal/acre, using a hand-operated CO2, sprayer operated at 3.2 kg/cm2 (45 lb/in2) and equipped with a Tee Jet D3 disc and No. 13 core. There were two exceptions: Sevin XLR was applied at 2.4 kg/cm2 (20 lb/in2) with a D2, 13 core at a rate of 54 1/ha (5.8 gal/acre); FCR 1272 was applied at 3.2 kg/cm2 (45 lb/in2) with a D3 disc, 13 core at 1870 1/ha (200 gal/acre). The ratio of water to Sevin XLR as 11:1. Visual observations were made on the 2.4 m (8 ft) of canopy between the trunks of the two vines from the east side of the row. Ratings were as follows: no live beetles = 0; 1-5 live beetles = 1; 6-10 beetles = 2; 11-15 beetles = 3; 16 or more live beetles = 4. In addition to repellency (presence) observations, treatments were also rated for feeding damage to foliage. This was accomplished by examining 10 shoots per treatment for beetle feeding. Each shoot was rated 0, 1, 2, 3, 4, or 5 depending on how many of the last five terminal leaves were damaged. Readings of 0 stood for no damage, 5 indicated feeding on all leaves. Ratings were totaled and compared by treatment.