Question

Which of the following shows the correct sequence of steps involved in breeding a new genetic variety of a crop?

a. Selection and testing of superior recombinants
b. Germplasm collection
c. Cross hybridisation among the selected parents
d. Evaluation and selection
e. Testing, release and commercialisation of new cultivars

• A. a, b, d, c and e
  
• B. b, c, a, d and e
• C. c, d, a, b and e
  
• D. b, d, c, a and e

Answer 1

The correct option is D b, d, c, a and e

Plant breeding
Plant breeding is a field of Biology where changing the traits of plants are done to produce desired characteristics in the progeny. It involves many steps.
Steps in plant breeding
The correct sequence of steps in plant breeding are as follows:
● Germplasm collection.
● Evaluation and selection of parents.
● Cross hybridisation among the selected parents.
● Selection of superior recombinants.
● Testing, release and commercialisation of new cultivars
Germplasm collection
Germplasm collection is a collection of the varieties of all available alleles of all genes present in a crop plant species. It is the first step of any plant breeding programme and helps to provide the breeders a wide array of different traits to exploit for the production of crop varieties with desirable combination of characteristics.
Evaluation and selection of parents
The whole available germplasm is screened for desirable traits that are to be incorporated into the new variety. The plants chosen as parents are self-pollinated (pollen from the anther of a flower is transferred to the stigma of the same flower or different flower of the same plant) to increase homozygosity (presence of similar alleles for a particular character). This results in the generation of a pure line.
Cross hybridisation among the selected parents
The process of hybridisation involves crossing between two pure line parents having desired characteristics with the help of artificial cross pollination (pollen from the flower of the plant designated as male parent is transferred to the stigma of the flower of the plant designated as female parent). The progeny obtained are called hybrids.
Selection of superior recombinants
The seeds produced by only those plants in the progeny, which show the desired combination of superior characteristics of both the parents, are selected for raising the future generation. This process is continued until the whole population exhibits the desired combination of superior characteristics.
Testing, release and commercialisation of new cultivars The new cultivars are first evaluated for their yield and other desirable qualities like disease resistance and tolerance to environmental stresses. The evaluation is performed by growing them in research fields under conditions like ideal fertiliser application and other crop management practises. The cultivars which successfully grow in the research laboratories are now grown in farmer’s fields for at least three growing seasons across different parts of the country representing the various agro climatic zones. The new cultivar is evaluated in comparison to the best available local crop cultivar in terms of quality and cost. Once the cultivar passes all the tests performed, it is released into the market.
Final answer
(A) b, d, c, a and e