Question

How can one do plant breeding for developing resistance to insect pests? Give a few examples to insect resistance characteristics. Also mention the source of pest resistance genes.

Answer 1

ANSWER:

Like disease, insects area unit necessary causative factors of organic phenomenon stress in crop plants. Insects attack all the crop plants and cause wide losses in yield moreover as quality. Insect attack results in varied sorts ofdamages. In crop plants like 1) Reduction in plant growth or acrobatics, 2) harm of vegetative and procreativeelements, 3) Premature defoliation, and 4) weakening of plants. Insect cause 14 July calculable yield loss of all necessary crops on international bases. Insect cause yield loss directly either by suck cell sap or by geological process varied plant elements. Insects additionally cause yield loss through transmission of assorted diseases.

There area unit 2 necessary ways of insect management, viz 1) biological technique and 2) chemical technique. In biological technique, insects area unit controlled in 3 ways, viz, 1) by the employment of predators and parasites of insect pests. 2) by victimization biology pesticides like margosa, Datura, Ipomea within the kind of leaf extracts, and 3) use of resistant varieties. Biological technique is affordable and doesn't have any adverse result on the system, through lesser effective than chemical technique of insect management. The chemical technique includes use of assorted chemical, pesticides. Use of pesticides has many disadvantages. It will increase value of cultivation, reduces population of predators and parasites of insect pests, results in environmental pollution and development of pesticides resistant biotypes of insects. so genetic resistance is that the most cost-effective and also the best technique of insect management in crop plants. Genetic resistance refers to the power of some genotypes to granthigher yields of fine quality than prone varieties at a similar initial level of insect attack beneath similar environmental conditions. so resistance is outlined in reference to prone varieties.

Host Crop	Insect Pest	Non-preference	Preference
Wheat	Strem Sawfly	Solid stem	Hollow stem
Rice	i)Rice stem borer	Lignified stem	Nonlignified stem