Arthropod Management Tests 2014, Vol. 39 doi: 10.4182/amt.2014.G7 (G7) BLUEGRASS (KENTUCKY): Poa pratensis L. RYEGRASS (PERENNIAL): Lolium perenne L. EVALUATION OF ACELEPRYN FOR CONTROL OF SOUTHERN MASKED CHAFERS, 2013 M. D. Stamm Department of Entomology University of Nebraska-Lincoln 103 Entomology Hall Lincoln, NE 68583-0816 Phone (402) 472-8702 Fax (402) 472-4687 Email: [email protected] L. S. Marchi Werle Phone: (402) 472-2123 Email: [email protected] K. G. Koch Phone: (402) 472-2123 E-mail: [email protected] T. J. Prochaska Phone: (402) 472-2123 Email: [email protected] Southern masked chafer (SMC): Cyclocephala lurid Bland Insecticides were evaluated for white grub control on a Kentucky bluegrass/perennial ryegrass rough at the North Bend Golf Course in North Bend, Nebraska. Products were applied on 28 May and 25 Jun to 5 x 5 ft turf plots; treatments were assigned to plots in a RCB design with 5 replications. All liquid products were applied using a CO2 sprayer at 40 psi and applying 87 gpa finished spray. Within 24 h following application, all treatments were irrigated with 0.25 inch of water. Formulations were evaluated 20 September (115 and 87 d after treatment (DAT)) by removing from each plot three, 8-inch diam turf-soil cores (1.05 ft² total area) to a depth of 3 inches and counting the no. of surviving grubs. The treatments were assessed weekly for phytotoxicity. Environmental conditions at the time of applications were as follows: soil moisture 10.9 and 9.0%, respectively; air temp 71 and 83ºF; soil temp 67 and 74ºF; relative humidity 78 and 57%; wind velocity 4 and 9 mph. All treatments provided statistically significant reductions in white grub numbers when compared to the untreated check. All Acelepryn 1.67 SC treatments provided acceptable (≥80%) white grub control. No phytotoxicity was observed at any of the assessments. Funding for this project was provided by industry grant in aid. Table 1. Treatment/ Formulation Acelepryn SC Acelepryn SC Acelepryn SC Merit 2F Merit 2F UTC Rate Application Mean No. WG % 2 Control fl oz/A Timing 1.05 ft 4 8 4 26 26 --- 28 May 28 May 25 June 25 June 28 May --- 0.6a 1.2a 1.4a 2.8a 3.2a 10.6b 94.3 88.7 86.8 73.6 69.8 --- Means followed by the same letter are not significantly different (P>0.05, LSD=3.2). 1