ENT207 Lecture Notes - Lecture 25: Bromomethane, Pyrethrum, Allethrins

• School: University of Alberta
• Department: Entomology (Biological Sciences)
• Course: ENT207
• Professor: Maya Evenden

Document Summary

Compare and contrast the different mechanisms of host plant resistance. Pest resistance is defined any inherited characteristic of a host that lessens effects of attack. Genetic resistance can be classified into three catagories: Nonpreference (antixenosis: plant characteristic that leads insects away from it, the principle is to interfere with normal insect behavior as a means lessening the insect"s chance in finding ovipositions sites, food or shelter. This is a chemical mechanism; the plant releases chemicals that deter insect feeding or laying of eggs. Cucurbitacins produces by cucrbits acts as a feeding incitant and cultivars lacking it attrack fewer beetles. As opposed to chemicals, this technique constitutes of physical deterrence. This type of antixenosis is defined as plant structures that deter feeding or oviposition. Prefers to oviposit on pubescent surface and so if cotton lacks hair surface then oviposition is reduced as is damage. Explain the importance of insect vectors in plant virus disease transmission;