1.

Chemical biological and silvicultural control of tree diseases

Answer»

Biological method of pest control requires knowledge of the life forms (predator + prey) that INHABIT a particular area, their life cycles, and patterns of FEEDING and preferred habitats. Example − Ladybirds and dragonflies are used to get rid of aphids and mosquitoes.

Microbes can also ACT in the same manner. BACILLUS thuringiensis (Bt) is used to control butterfly caterpillars. This bacterium is available in sachets as dried spores, which are sprayed on the crops. The spores get into the gut of the larvae and kill it while the other insects remain unperturbed.

By methods of genetic engineering, the genes of B. thuringiensis responsible for killing the larvae have been INCORPORATED into the plants. Cotton plant with Bt gene incorporated is called Bt-cotton. The fungus Trichodermaliving in roots of plants acts as a bio control agent against several plant pathogens.


Discussion

No Comment Found

Related InterviewSolutions