Submitted to: Entomology International Congress Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 8/20/2000
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Scarabs are a major pest in North America infesting turfgrass, ornamental nursery stock, sugarcane, corn and sweet potato. Most species are univoltine, but some species have two to three year life cycles. The IPM of scarabs begins with the monitoring of adult beetles using light/pheromone traps. Cultural practices, such as reduction in the frequency of irrigation at the time of peak flight activity help reduce egg survival. The newly hatched grub larvae are the targets of the recently registered pesticides, imidacloprid and halofenozide. Both insecticides provide 90-100% control of the most common Japanese beetle, Popillia japonica, grubs when applied at the first and second instar stage, but are not effective against the third/last instars. Our research indicates that there is a strong synergism between entomopathogenic nematodes and imidacloprid against third instar scarabs of several species. Field tests indicate that the application of one-third rate of imidacloprid in combination with one-half the nematode standard rate would provide acceptable curative grub control in turfgrass. In another project, we have discovered that there is synergism between fungal endophytes of grasses and entomopathogenic nematodes against P. japonica grubs. Synergism between the milky disease pathogen, Paenibacillus popillae, and entomopathogenic nematodes has also been demonstrated by other researchers. Therefore, there are good prospects for the development of biologically-based IPM approach for scarabs in North America.