Author
Klein, Michael |
Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 8/9/1996 Publication Date: N/A Citation: N/A Interpretive Summary: Adults and larvae (white grubs) of scarab beetles can be serious pests of field crops, ornamental plants and flowers, and turf throughout the world, and are likely to increase in significance with the loss of chemical insecticides and concerns about the environment. Numerous workers throughout the world are searching for biological control agents such as bacteria as replacements for conventional pesticides. This book presents techniques for the isolation, identification, propagation and production, bioassay and evaluation, and preservation and storage of many groups of insect pathogens. This chapter examines methods for handling bacteria which kill white grubs in their soil environment. Three bacteria: the common insect pathogen Bacillus thuringiensis (BT); the milky disease bacteria; and the bacteria causing amber disease in New Zealand grass grubs, are covered. Detailed descriptions and pictures of pathogens, techniques, formulas, and media for working with these bacteria are presented. The Handbook, and this chapter, will enable workers to utilize proper methods in various situations and allow maximum development of bacteria as insect pathogens. This information will be valuable to scientists world wide who are seeking to find alternatives to pesticides against scarab pests, and ultimately will provide homeowners and consumers with safer pest control methods. Technical Abstract: The adults and larvae of scarab beetles are serious pests of crops, ornamentals, and turf throughout the world, and are likely to increase in significance with the loss of conventional chemical insecticides. In addition, pests like the Japanese beetle, Popillia japonica, are quarantined to prevent introduction and damage in new areas as has occurred in the United States and the Azore Islands. Surveys of the general status of pathogens against scarabs indicate that bacteria are the most important pathogens for these pests. However, recent reviews examined the status of bacteria against turf and soil pests in general and concluded that despite their importance, and concerns about environmental contamination, there are few microorganisms available for use against soil-inhabiting pests. This chapter concentrates on three groups of bacteria, two Bacillus species (B. thuringiensis and B. popilliae) and the genus Serratia, and describes methods for their isolation, identification, propagation, bioassay, and preservation. Bacillus thuringiensis is the most widely used pathogen for control of insects and is just being developed for scarab larvae. Both B. thuringiensis and Serratia, the causal agent of amber disease in the New Zealand grass grub, grow on common microbiological media. Bacillus popilliae, which causes milky disease in scarab larvae, requires specialized media and techniques. Detailed methods and media are presented for all three bacteria. |