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Listronotus maculicollis Kirby is a highly destructive pest of low mown, cool-season turfgrasses in the northeastern United States and Canada. Behavioral and electrophysiological assays were conducted to identify compounds that may be useful in developing novel monitoring techniques. In Y-tube assays, males and females responded differently to volatiles from intact and clipped annual bluegrass (Poa annua L.). Females were signiÞcantly attracted to intact P. annua but repelled from clippings; males did not respond signiÞcantly to either treatment. Electroantennogram (EAG) re- cordings from both sexes showed a signiÞcant response to volatiles from both treatments. Gas chromatography mass spectrometry (GC-MS) identiÞed 12 volatile compounds from P. annua of which nine were common to both intact plants and clippings. On average, seven-fold higher quantities of volatiles were collected from clippings than from intact plants (24.3 versus 3.4 ng/g of tissue/h). Eight compounds were released in signiÞcantly greater quantities from clippings of which 50% were the n-C6 compounds hexanal, (E)-2-hexenal, and (Z)-3-hexenyl acetate, commonly referred to as "green leaf volatiles" (GLVs). Only octanal was emitted in greater amounts from intact plants than clippings. These nine compounds were tested individually against male and female antennae. Both sexes displayed greatest sensitivity to nonanal, octanal, and (E)-2-hexenal, but a signiÞcant doseÐ response relationship was observed with all compounds tested. These studies indicate that both sexes respond physiologically and that L. maculicollis females exhibit behavioral responses to host-plant volatiles. Future studies will need to assess the effects of individual compounds and component mixtures on L. maculicollis behavior in the Þeld.

Wax-based pelleted sex pheromone formulations were tested for efficacy in managing oriental beetle, Anomala orientalis Waterhouse, in turfgrass. Four pellet formulations were field tested at 25 g pheromone/ha during 2006 and 2007. Application patterns included pellets specifically placed in a uniform grid pattern and pellets scattered by a broadcast spreader. Treatment efficacy was measured by monitoring male A. orientalis captures in pheromone-baited traps, determining mating success of confined virgin females, and estimating subsequent densities of A. orientalis larvae in soil/sod samples. All formulation and application pattern combinations effectively suppressed mating for 2 wk after application as measured by reduction in male trap captures and mating success of confined virgins. Two formulations gradually lost efficacy beginning 2 wk after application and the two others after 3-4 wk. Application pattern had no effect on trap captures. The most effective formulation reduced trap captures by/=90% for 36 d, reduced mating success of confined females by 86-100% until 24 d after treatment, and reduced A. orientalis larval populations by 69%. In a previous study, sprayable formulations resulted in nuisance contamination of shoes that attracted male beetles outside of pheromone-treated areas. In contrast, shoes walked through pellet-treated areas did not attract male beetles. Pellet formulations have great potential for A. orientalis mating disruption, but more research is needed to optimize performance.

The feasibility of mating disruption in the oriental beetle, Anomala orientalis Waterhouse, with microencapsulated sprayable formulations of (Z)-7-tetradecen-2-one, the major sex pheromone component, was evaluated in turfgrass areas. The effect of the applications was measured by monitoring male A. orientalis captures in pheromone-baited traps throughout the flight period and estimating A. orientalis larval densities in September in soil/sod samples. Trap captures were 90–100% lower in the treated areas during the first 7–10 d after treatment, but started to increase thereafter. Therefore, applications were repeated after 14 d in most treatments. The formulation tested in 2002 and 2003 reduced trap captures by 87–88% with two applications of each 12.5 or 50 g pheromone/ha but only by 74% by a single application of 75 g pheromone/ha. Reductions of A. orientalis larval populations by 68–74% were not significant because of very high variability of larval densities in the nontreated areas. Two differ...

Previous observations on the effect of endophyte infection in turfgrass on white grub development and natural incidence have been variable and contradictory. We reexamined these white grub-endophyte interactions and expanded them to the previously not studied oriental beetle (Exomala [= Anomala] orientalis Waterhouse). Endophyte infection in strong creeping red fescue (Festuca rubra L. rubra) had no effect on survival and weight gain of neonate Japanese beetle (P. japonica Newman) and E. orientalis larvae in greenhouse pot experiments. In tall fescue (Festuca arundinacea Schreber) in greenhouse pot and in microplot field experiments, endophyte infection had no significant effect on survival and a weak negative effect on weight gain of P. japonica, but reduced E. orientalis survival without affecting its weight gain. In samples taken from tall fescue fields in October, the natural incidence of third instars was higher in endophytic than in nonendophytic turf in 3 of 4 yr. The effect was strongest ...

We evaluated the effect of endophyte infection in the two turfgrasses tall fescue (Festuca arundinacea Schreber) and strong creeping red fescue (F. rubra L. ssp. rubra) on the susceptibility of three white grub species to the entomopathogenic nematode Heterorhabditis bacteriophora Poinar. Endophyte infection in strong creeping red fescue (only tested under greenhouse conditions) had no effect on nematode-susceptibility of third-instar oriental beetle (Exomala (=Anomala) orientalis Waterhouse) and northern masked chafer (Cyclocephala borealis Arrow). In tall fescue under greenhouse conditions, endophyte infection had a weak and variable enhancing effect on nematode-susceptibility of second- and third-instar E. orientalis and no effect on nematode susceptibility of third-instar C. borealis and Popillia japonica. However, under field conditions with natural white grub populations, endophyte infection in tall fescue had no significant effects on nematode efficacy against E. orientalis, P. japonica, and C. borealis. While it is possible that stronger interactions between endophytes and nematodes may occur with different grass species, cultivars, and endophyte strains, nematode-endophyte interactions appear to be too variable to allow predictions on nematode efficacy based on turfgrass endophyte status.