Question

Which of the following is generally used for induced mutagenesis in crop plants?

• A. X-rays
• B. UV (260 nm)
• C. gamma rays (from cobalt 60)
• D. alpha particles.

Answer 1

Answer: (C)

gamma rays (from cobalt 60)

Answer 2

Among the physical mutagens, X and $\gamma$ rays are the most commonly used mutagens in mutation breeding. Over the past 40 years use of $\gamma$ rays in mutation induction has become particularly prevalent, while the use of X-rays has significantly reduced. The preference for $\gamma$ rays is probably on account of both its wide availability and versatility of use. The naturally occurring isotope K40 is one source of $\gamma$ rays in the environment.For practical purposes, Co60 and Cs137 are used as their physical parameters like half life, energy of rays produced etc. make them suitable as gamma source.