Question

Functions of plant growth promoters and plant growth inhibitors are given here in a jumbled up manner. Select the option that correctly segregates these functions.

I. Cell division

II. Cell enlargement

III. Pattern formation

IV. Tropic growth

V. Flowering

VI. Fruiting

VII. Seed germination

VIII. Response to wound

IX. Response to stresses of biotic and abiotic origin

X. Dormancy

• A. $\begin{array}{ccc}& \text{Functions of growth promoters}& \text{Functions of growth inhibitor}\\ & \text{I, II, VII, IX}& \text{III, IV, V, VI, VIII, X}\end{array}$
• B. $\begin{array}{ccc}& \text{Functions of growth promoters}& \text{Functions of growth inhibitor}\\ & \text{VIII, IX, X}& \text{I,II,III, IV, V, VI, VII,}\end{array}$
• C. $\begin{array}{ccc}& \text{Functions of growth promoters}& \text{Functions of growth inhibitor}\\ & \text{I, II, III, IV,V, VI VII,}& \text{VIII,IX,X}\end{array}$
• D.
  $\begin{array}{ccc}& \text{Functions of growth promoters}& \text{Functions of growth inhibitor}\\ & \text{I, II, III, IV, V, VI VII, IX, X}& \text{VIII}\end{array}$

Answer 1

The correct option is C $\begin{array}{ccc}& \text{Functions of growth promoters}& \text{Functions of growth inhibitor}\\ & \text{I, II, III, IV,V, VI VII,}& \text{VIII,IX,X}\end{array}$

Plant growth hormones (PGRs) or phytohormones are the organic substances which are synthesised in minute quantities in one part of the plant body and transported to another part where they influence specific physiological processes. The plant growth hormones are broadly divided into two groups:

a) Plant growth promoters

b) Plant growth inhibitors.

Plant growth promoters perform growth-promoting activities like cell division, cell enlargement, pattern formation, tropic growth, flowering, fruiting and seed formation. They are three in number viz., auxins, gibberellins and cytokinins.

Plant growth inhibitors have important functions in inducing plant responses to wounding, biotic and abiotic stresses, dormancy and abscission. Ethylene is largely plant growth inhibitor but is also involved in some growth promotion activities.