Biological Control Agents for White Grubs (Coleoptera: Scarabaeidae) in Anticipation of the Establishment of the Japanese Beetle in California

Abstract

We tested biological control agents for the control of 3rd-instar scarab turfgrass pests, both for the masked chafer Cyclocephala hirta LeConte and the Japanese beetle, Popillia japonica Newman. The former species is endemic in California whereas the latter, although not yet established, constitutes a permanent serious threat to agriculture and horticulture in California. We conducted experiments using C. hirta in California and P. japonica in New Jersey. A field trial conducted in 2 different California turfgrass sites compared the field persistence in the absence of hosts of Bacillus thuringiensis Berliner subspecies japonensis Buibui strain, the milky disease bacterium, Paenibacillus (=Bacillus) popilliae (Dutky), and the entomopathogenic nematodes Steinernema kushidai Mamiya and Heterorhabditis bacteriophora Poinar to that of the organophosphate diazinon. Soil samples taken 0-70 d after applications were bio-assayed with P. japonica. Only diazinon and the entomopathogenic nematode S. kushidai caused substantial mortality and S. kushidai activity persisted significantly longer than diazinon activity. In greenhouse experiments, combinations of entomopathogenic nematode species usually resulted in additive mortality of scarab larvae. Combinations of S. kushidai and diazinon also resulted in additive mortality. In field trials, the efficacy of H. bacteriophora and especially S. kushidai and S. glaseri, was comparable to that of diazinon over 14-18 d. However, it is likely that at least S. kushidai would have outperformed diazinon over an extended period because of its longer persistence and potential for recycling in the hosts. S. kushidai, should it become commercially available, deserves further examination as an alternative to chemical white grub control especially as a highly compatible component of sustainable turfgrass management.

Effects of Pink Bollworm Resistance to <I>Bacillus thuringiensis</I> on Phenoloxidase Activity and Susceptibility to Entomopathogenic Nematodes

“…Previous simulation modeling suggests that such refuges would be more effective at delaying pest resistance to Bt crops than refuges that do not impose Þtness costs (Carriè re and , Pittendrigh et al 2004). An additional beneÞt of using nematodes to increase Þtness costs is that these organisms also can serve as biological control agents (Gouge et al 1999, Journey and Ostlie 2000, Koppenhö fer et al 2000, thereby decreasing the need for conventional insecticides to manage pest populations in refuges. Consequently, entomopathogens may present an opportunity to integrate resistance management with biological control through the use of pest control agents that also delay the evolution of resistance to Bt by magnifying Þtness costs.…”

Synopsis of the cyclocephaline scarab beetles (Coleoptera, Scarabaeidae, Dynastinae)

“…Milky disease, caused by the bacterium Paenibacillus popilliae Dutky (Bacillales: Paenibacillaceae), is the only registered biological control specifically for P. japonica (Koppenhöfer et al 2000). Infections of the disease are chronic in populations, but infection rates grow slowly (Klein 1992).…”

Susceptibility of the Japanese beetle, Popillia japonica (Newman) (Coleoptera: Scarabaeidae), to entomopathogenic Hypocreales fungi

“…Several microbiological agents have been studied for their potential to regulate larval populations of the Japanese beetle, including the bacteria Bacillus thuringiensis serovar japonensis strain Buibui (Ohba et al 1992;Alm et al 1997;Koppenhofer et al 2000;Bixby et al 2007), B. thuringiensis subsp. galleriae SDS-502 (Yamaguchi et al 2013) and Paenibacillus popilliae (formely Bacillus popilliae) (Bulla et al 1975;Klein 1992;Redmond and Potter 1995;Matsuki et al 1997;Rippere et al 1998), the nematodes Steinernema glaseri Steiner and Heterorhabditis bacteriophora Poinar, and the fungi Metarhizium anisopliae (Lacey et al 1994;Villani et al 1994;Lacey et al 1995b;Abalos et al 2001;Cappaert and Smitley 2002;Petty et al 2012) and Beauveria bassiana (Hanula and Andreadis 1988;Hanula et al 1991;Klein 1992;Lacey et al 1995a, b;Bixby et al 2007).…”