In mutation breeding, which of the following does NOT represent chemical mutagens?

Step-by-step solution

Mutation breeding involves inducing mutations to develop new plant varieties with desirable traits. This can be achieved using physical or chemical mutagens. Chemical mutagens include alkylating agents like methyl methane sulphonate (MMS), base analogues, and other compounds like sodium azide and hydroxylamine that alter DNA structure. Colchicine is an alkaloid used primarily to induce polyploidy by inhibiting spindle fiber formation during cell division. While it causes genetic changes (changes in chromosome numbe