Biodiversity and its Conservation Question 40
40. In mung bean, resistance to yellow mosaic, virus and powdery mildew were brought about by :
(a) Hybridisation and selection
(b) Mutation breeding
(c) Biofortification
(d) Tissue culture
Show Answer
Answer : b
Hints & Solutions
(b) Mutation is the process by which genetic variations are created through changes in the base sequence within genes resulting in the creation of a new character or trait not found in the parental type. It is possible to induce mutations artificially through use of chemicals or radiations (like gamma radiations), and selecting and using the plants that have the desirable character as a source in breeding, this process is called mutation breeding. This procedure has helped mung bean production by providing resistance against yellow mosaic virus and powdery mildew (fungal disease). yellow mosaic virus symptoms: Initially small yellow patches or spots on the young leaves. Slowly yellow discoloration increases and the entire leaf may turn yellow. Infected leaves show alternating green and yellow patches. Yellow leaves turn slowly dry and wither. Powdery mildew is a fungal disease that affects a wide range of plants. Powdery mildew diseases are caused by many different species of fungi in the order Erysiphales, with Podosphaera xanthii (a.k.a. Sphaerotheca fuliginea) being the most commonly reported cause.
