PESTICIDE RESISTANCE IN FLORIDA INSECTS LIMITS MANAGEMENT OPTIONS

Pesticide resistance in Florida was characterized through a survey and literature review The survey was conducted in 1994 among public-secto r entomologists to determine the current and future status, extent, co ntext, pattern, and instances of pesticide (insecticide and acaricide) resistance in Florida. Results attested to the impact of pesticide re sistance on the management of numerous arthropods in Florida. Twenty-f ive examples of insecticide and acaricide resistance were cited by sur vey respondents in agricultural, ornamental and landscape, medical and veterinary, or household and structural pests. It remains possible to manage most arthropods by using chemical pesticides, but the current and anticipated lack of efficacious materials threatens current practi ces in some areas. Trends in extent, context, or patterns of resistanc e were noted as follows: high value crops, frequently treated arthropo ds, smaller arthropods, and pyrethroids were all considered factors as sociated with resistance. Insecticide resistance and its management we re reviewed in depth for the leafminer Liriomyza trifolii and the diam ondback moth, Plutella xylostella, two major insect pests in Florida f or which management options have become severely limited because of in secticide resistance. Both cultural practices (continuous cropping, is olation, transport of infested seedlings) and pesticide use patterns ( frequent application of broad spectrum pesticides) contributed to L. t rifolii and P. xylostella I resistance development. The history of pes ticide resistance in these two insects is probably typical of pest res istance in Florida and may portend similar future problems unless depe ndency on pesticides for pest suppression is reduced through adoption of IPM philosophy and practices.