pesticide is any substance or mixture of substance intended for preventing, destroying, repelling or mitigating any pest. More than 500 different species of arthropods are resistant Pesticides used have led to the development of insecticide resistance. Development of insecticide resistance populations is a typical evolutionary process driven by survival of the fittest individuals.
GENERALIZED PROCESS OF INSECTICIDE
OVERVIEW OF RESISTANCE MECHANIMS
The intoxication insecticide by the insect 1. Penetration of barrier tissues 2. Distribution, storage, and metabolism in internal tissues 3. Molecular interaction with the ultimate target site
Mutations that affect the rate constants of any these processes may reduce either the delivery of the ultimate toxicant to its target or the affinity of the toxicanttarget interaction
Reduced cuticular penetration of toxicants Enhanced oxidative metabolism by cytochrome P450 dependent monooxygenases, hydrolases, or glutathione-S-transferases Reduced sensitivity of mutant acetlycholinesterases to Organaphosphate and Carbamate insecticides.
of amino acids responsible for insecticide binding at its site of action cause the insecticide to be less effective or even ineffective.
enzymes responsible for detoxification of xenobiotics in living organisms are transcribed by members of large multigene families of esterases, oxidases, and GST
A. Single amino acid mutation in the IIS6 membrane-spanning region of the sodium channel gene that confers target-site DDT-pyrethroid resistance
B. Regulatory element allows induction of insecticide detoxifying oxidase and esterase resistance genes C.Esterase A2-B2 amplicon. These resistance esterase genes lie 5' end to 5' end within the same amplification unit
understanding of Molecular Mechanism of Insecticide Resistant is very important for the management of Insect Pests.