Question

What are somaclonal variations and what are the prospects of their use in crop improvement programs?

Answer 1

Hint: Somaclones are genetically identical plants that can be produced from cells of somatic origin. It is produced from the vegetative plant parts, majorly through the process of tissue culture.

Complete answer:Somaclonal variations are genetic variations observed among the plants that are produced through somatic cells via in-vitro culture.
The various applications or prospective uses of somaclonal variations in crop improvement programs are as follows:
Production of agriculturally useful crops or plants-Through this process, several new useful varieties of crops can be produced such as sugarcane with high sugar content, soybean with high protein and oil content and carrot with high carotene content.
Increases disease resistance- This process produces disease-resistant varieties of many crops, thus increasing the yield. It includes crops such as rice, wheat, tobacco, apple, sugarcane, etc.
Providing resistance to abiotic stresses-Abiotic stresses includes temperature and chemicals present in the soil. Various crops produced through this technique that developed resistance are carrots and tomatoes against aluminium. Rice and maize developed resistance against salt and wheat against cold.
Resistance to herbicides-This process has led to the development of immunity against various herbicides. Crops that developed resistance include Tobacco to glyphosate, sulfonylurea, and picloram and carrots to glyphosate.
Improved quality of the seeds produced-It increases the seed quality that can provide an advantage in increasing the yield of the crops.

Note: The various causes for somaclonal variations can be due to mutations which newly arises during the process of tissue culture. The mutations are widely caused by various stress factors such as the chemicals used in sterilization, high concentration of growth factors or plant hormones in the tissue culture media such as auxins and cytokinins and lighting conditions.