Host plant acceptance by redlegged earth mite, Halotydeus destructor (Tucker) (Acarina: Penthaleidae)

Host plant acceptance behavior of redlegged earth mites (Halotydeus destructor) on cotyledons of subterranean clover (subclover) lines was investigated in the laboratory. Sustained feeding consisted of a series of short bouts of feeding; rather than one long period of feeding. H. destructor preferred to feed at mite-damaged rather than undamaged sites on cotyledons. With time the numbers of mites feeding in aggregations increased, as mites were attracted to damaged patches. Most feeding occurred in aggregations, and mites in such groups benefited by greater weight gain. The sequence of foraging leading to feeding was similar between subclover lines, however, feeding and aggregation activities were markedly reduced on a resistant line. Host plant acceptance occurred during probing but only after some feeding had occurred.