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Desirable characteristics of a crop variety helps in easy adoption of that crop by the farmers. In this context, consider the following statements:

1. Incorporating desirable characters into crop varieties can be done through fertilisation.

2. Dwarfness is desired in cereals, so that less nutrients are consumed by these crops.

3. Hybridisation refers to crossing between genetically similar plants.

Which of the statement(s) given above is/are correct?

(A)

1 and 2 only

(B)

2 only

(C)

1 and 3 only

(D)

1, 2 and 3

Explanation:

ANSWER: (B)

Statement 1 and 3 are not correct.

One way of incorporating desirable characters into crop varieties is by hybridisation. Hybridisation refers to crossing between genetically dissimilar plants.
This crossing may be inter-varietal (between different varieties), interspecific (between two different species of the same genus) or intergeneric (between different genera).
Another way of improving the crop is by introducing a gene that would provide the desired characteristic. This results in genetically modified crops.
For new varieties of crops to be accepted, it is necessary that the variety produces high yields under different conditions that are found in different areas.

Statement 2 is correct.

Cultivation practices and crop yield are related to weather, soil quality and availability of water. Since weather conditions such as drought and flood situations are unpredictable, varieties that can be grown in diverse climatic conditions are useful. Similarly, varieties tolerant to high soil salinity have been developed.
Some of the factors for which variety improvement is done are:
Desirable agronomic characteristics: Tallness and profuse branching are desirable characters for fodder crops. Dwarfness is desired in cereals, so that less nutrients are consumed by these crops. Thus, developing varieties of desired agronomic characters help give higher productivity.
Higher yield: To increase the productivity of the crop per acre.
Improved quality: Quality considerations of crop products vary from crop to crop. Baking quality is important in wheat, protein quality in pulses, oil quality in oilseeds and preserving quality in fruits and vegetables.
Biotic and abiotic resistance: Crops production can go down due to biotic (diseases, insects and nematodes) and abiotic (drought, salinity, water logging, heat, cold and frost) stresses under different situations. Varieties resistant to these stresses can improve crop production.
Change in maturity duration: The shorter the duration of the crop from sowing to harvesting, the more economical is the variety. Such short durations allow farmers to grow multiple rounds of crops in a year. Short duration also reduces the cost of crop production. Uniform maturity makes the harvesting process easy and reduces losses during harvesting.
Wider adaptability: Developing varieties for wider adaptability will help in stabilising the crop production under different environmental conditions. One variety can then be grown under different climatic conditions in different areas.