Plant Growth And Development Ques 74

74. The regulator which retards ageing/senescence of plant parts is :

(a) cytokinin

(b) auxin

(c) gibberellin

(d) abscisic acid

Show Answer

Answer : a

Hints & Solutions

(a) Cytokinins help in retaining chlorophyll, hence delay senescense. Cytokinin deficiency causes slow growth of the shoot and morphological changes such as dwarfism and smaller leaves. It has been shown previously that SAMs of cytokinindeficient plants are smaller because of reduced cell numbers.