Question

13. In micropropagation, an undesirable result from placing a shoot tip explant on medium is

• a. callus at base of stem
• d. roots at base of stem
• c. multiple shooting from lateral buds in stem
• b. continued growth of the explant as a single shoot

Answer 1

Solution

In micropropagation, an undesirable result from placing a shoot tip explant on medium is:

a. callus at base of stem

At the base of the stem rooting is supposed to take place. The development of basal callus affects the rooting competence of the microplants. The callus becomes a physical barrier as well as a sink for plant growth regulators, entrapping them to interefere with many physiological processes responsible for plant growth.

Root formtion at the base of the stem, multiple shooting from lateral buds and continued growth of the explant as a single shoot ( can be used for excising to obtain nodal explants which can be cultured in cytokinin-rich media for multiple shoot proliferation) are all advantageous for micropropagation.