INSECT PEST CONTROL Current status problems and why

INSECT PEST CONTROL Current status, problems and why a new approach is necessary

Crop Pests: Some issues • • • Imbalance leads to pest development human intervention leads to imbalance dynamic interaction crop and pest importance of key pests living with pests or not quarantine Crop Losses due to Insects/Weeds/Diseases Then and Now 1965…. 34. 9% 2000…. . 42. 1%

Insect Pests, Food Production and Diseases WHAT IS A PEST ? WHY BECOME A PEST ? DEALING WITH PESTS 1, 000 SPECIES 1000 PESTS 10 KEY PESTS

Traditional Strategies CHEMICAL BIOLOGICAL i g n fu es d i c ecti ins JH attractants s n toxi ana logu dyes es pa ras phe ne ma rom ito ids es s rs o t a red p tod one

Current Constraints to Insect Control Technical Issues Social Issues RESISTANCE ENVIRONMENT NON-TARGET EFFECTS BIODIVERSITY Scientists Public

Pest Control Philosophies THERAPEUTIC INTERVENTIONS SYSTEMS MANAGEMENT Magic bullet Integrated P. M. Farm by farm Area-wide Farmer Collective Reductionist Holistic Local Population Accomodation Total Population Eradication

Insect Vectors of Disease Interventions pathogen THE ETERNAL TRIANGLE insect Diseases host Drugs Insecticides Genes Vectors Malaria 300 M cases Anopheles species Filiariasis 250 M infected Culex, Aedes, Simulium Trypanosomosis 10, 000/year Glossina species Chaga’s disease 24 M infected Triatoma and Rhodnius spp Leishmaniasis 400, 000/year Lutzomyia and Phlebotomus

Insecticides 2. 6 M tons of active ingredient in 1995 500 species resistant environ/social cost US$ 8 B secondary pests 74% more OP 1979 -1981 biological Consequences economical

Insecticide Resistance Probit Mortality DOSE 1 SS RS DOSE 2 RR Mechanism Detoxification Target Site Change Reduced Penetration Log Pesticide Dose Genetic Basis Gene Amplification Gene Mutation ? ? ?

SUMMARY • • Insects become pests due to man Key pests, quarantine and imbalance Technical/social constraints Therapeutic interventions vs systems approach • Insect vectors and the eternal triangle • Insecticides and resistance