Explain the main steps involved in the breeding of a new genetic variety of crop plants.

Explanation

(i) Collection of variability : Collection and preservation of all the different wild varieties, species and relatives of the cultivated species ( followed by their evaluation for their characteristics ) is a pre requisite for effective exploitation of natural genes available in the populations.
(ii) Evalution and selection of parents : The germplasm is evaluated so as to identify plants with desirable combination of characters. The selected plants are multiplied and used in the process of hybridization. Purelines are created wherever desirable and possible.
(iii) Cross hybridization among the selected parents : The desired characters have very often to be combined from two different plants ( parents), for example high protein quality of one parent may need to be combined with disease resistance from another parent. This is possible by cross hybridizing the two parents to produce hybrids atat genetically combine the desired characters in one plant.
(iv) Selection and testing of superior recombinants : This step consists of selecting, among the progeny of the hybrids, those plants that have the desired character combination. This step yields plants that are superior to both of the parents. These are self-pollinated for several generations till they reach a state of uniformity ( homozygosity), so that the characters will not segregate in the progeny.
(v) Testing release and commercialization of new cultivars : The newly selected lines are evaluated for their yield and other agronomic trails of quality, disease resistance, etc. This evalution is done by growing these in the research field and recording their performance under ideal ferlilizer application, irrigation, and other crop management practices.