Question

Induction of rooting in stem cutting would be most beneficial in
A) Marchantia
B) Wheat
C) Cuscuta
D) Bougainvillea

Answer 1

Hint: Auxin is a phytohormone that initiates rooting in stem cuttings. High concentrations of auxin inhibit root elongation and instead enhance adventitious root formation.

Complete Answer:
To solve this question, we must know about the plants which can be propagated by stem cuttings as well as the hormone responsible for rooting effects.
A) Marchantia is a member of the Marchantiaceae, the Marchantia family. This family belongs to one of many thalloid liverwort families. A thalloid liverwort is a strap-like in the structure which forms large colonies on the surface where it grows. Liverwort is a nonvascular green plant. Marchantia is able to reproduce both sexually and asexually. Sexual duplicate includes sperm from antheridia at the male plant fertilizing an ovum (egg cell) withinside the archegonium of the female plant. The sporophyte produces spores which become free-dwelling male and female gametophyte plants.

B) Wheat is an angiosperm which reproduces sexually. They have their seeds in a protective ovary (fruit) and are not "naked" like a gymnosperm seed.

C) Cuscuta campestris grows by seeds which are dispersed by wind, water, birds, other animals, and by man. C. campestris reproduces by seeds that germinate under relatively high temperatures. The seeds can remain viable for a period of more than 3 years.

D) Bougainvillea comprises a genus with thorny ornamental vines, trees or bushes. Its flowers are specifically propagated with the aid of using stem cuttings.
Auxin is a plant hormone involved in growth and developmental processes of the plant. It stimulates rooting in stem cuttings. Hence, induction of rooting in stem cutting would be most beneficial in Bougainvillea.

Thus, the correct answer is option (D) Bougainvillea.

Note: Bougainvillea can also be propagated by seeds. The colours of the plant are due to the bracts but not the flowers.