Evaluation of Entomopathogenic Nematodes for Control of White Grubs on Golf Course Fairways in Wv, 1992

Abstract

Abstract Two tests were conducted. Test 1 (Clarksburg C.C.) was installed 3 Aug. Environmental conditions were; air temperature, 31°C; RH, 72%; partly sunny (calm); soil temperature (2 inches), 25°C; pH, 4.77; organic matter, 8.13%; soil moist; soil type, loam (sand 42.6%, silt 43.4%, clay 14.0%); thatch layer 1/4 inch (compressed). Total precipitation during the trial period was 1.35 inches. Treatments were applied in mid-morning from 1000 to 1045h. Nematodes were applied in with a sprinkler can in 2.5 liters of water then irrigated with 2.0 liters about three min after application (water pH, 6.80; temperature, 22°C). Pretreatment population counts averaged 21.6 larvae/ft2 and were mainly 1st instars (100% Japanese beetle). Test 2 (Deerfield C.C.) was installed 26 Aug. Environmental conditions were: air temperature, 24°C; RH, 81%; overcast (fog); soil temperature (2 inches), 28°C; pH, 4.55; organic matter, 10.10%; soil moist; soil type, silt loam (sand 22.2%, silt 64.1%, clay 13.7%); thatch layer 1/8 to 3/8 inches (compressed). Total precipitation during trial period was 3.90 inches. Treatments were applied in the morning from 0830 to 0920 h. Plots were irrigated with about two liters of water, nematodes then applied with a sprinkler can in 2.5 liters, then irrigated with about 3 liters of water about three min after application (water pH, 6.90; temperature, 23°C). Pretreatment population counts averaged 37.7 larvae/ft2 and were 1st and 2nd instars (73% Japanese beetle, 27% northern masked chafer). Both tests; experimental design was a RCB with 4 replications; plots were 8 x 8 ft with a 2 ft buffer zone between; plots were sampled with a cup changer (4.25 inches diam) to a depth of 2-3 inches (4 samples per plot).