Briefly describe various steps involved in plant breeding.
The main steps in plant breeding are
(i) Collection of variability and evaluation of traits Genetic variability lies at the heart of any breeding program.
All different wild varieties/species and relatives of the cultivated . species are collected, evaluation for their characteristics are preserved so that this genetic pool can be used.
The entire collection (of plants/seeds) having all the diverse alleles for all genes in a given crop is called germplasm collection.
(ii) Selection of parents Plants with desirable combination of characters are selected, multiplied and used in the process of hybridization.
Purelines are created (by repeated inbreeding) wherever desirable and possible.
(iii) Cross hybridisation among the selected parents Two different plants with desired characters may be combined to form hybrids with both traits, e.g., high protein quality of one parent may need to be combined with disease resistance from another Parent.
(Iv) Selection and testing of superior recombinants From the progeny of the hybrids, plants with desired character combinations are selected, self-pollinated for, several generations till they become uniform or homozygous.
(v) Testing, release and commercialisation of new cultivars The newly 'selected lines are evaluated for their yield and other agronomic trails (of quality, disease resistance, etc.) by
(a) growing these In the research fields and
(b) recording their performance under ideal fertiliser application, irrigation and other crop management practices.
(vi) Actual farm testing .Final step involves testing the generated varieties
(a) In farmers' fields.
(b) for at least three growing seasons.
(c) at several locations in the country, represenling all the agro-climatic zones, where the crop is usually grown.
These are evaluated in comparison to the best available local crop cultivar; a check or reference cultivar.