Can gamma rays used for crop improvement programmes prove to be harmful for health? Discuss.
No radiation treatment has been used to create thousands of new plant varieties. These varieties are cultivated as food and feed. Radiation is known to be much more disruptive for chromosomal structure than the manipulations used to make transgenic plants.
Such radiation treatment of crop plants has caused no documented instances of ill-health among consumers despite having been used commercially for several decades.
For rice crops alone, hundreds of different mutant varieties have been developed mostly made by using ionising radiations, like gamma rays.
In animal husbandry, if two closely related animals are mated for a few generations, it results in loss of fertility and vigour. Why is this so?
The loss in fertility and vigour occurs after inbreeding because the recessive alleles tend to get together and express harmful effects in the progeny.
In the area of plant breeding, it is important not only to preserve the seeds of the variety being cultivated, but also to preserve all its wild relatives. Explain with a suitable example.
Collection and preservation of all the different wild varieties, species and relatives of the cultivated species is a important for effective exploitation of natural genes available in the population. e.g., sources of resistance genes may be cultivated varieties, germplasm collections of the crop or wild relatives.
Name a man-made cereal. Trace how it was developed and where is it used?
Triticale is a man-made cereal. It was developed by crossing Triticum aestivum (common wheat) and Secale cereale (European rye).
Triticale seed grain is being used in some parts of the world as a wheat substituted.
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