Read the following statements.

(a) Kinetin occur naturally in plants .

(b) Cytokinin help to overcome the apical dominance. 

(c) Influences of ABA on plants include horizontal growth of seedlings, swelling of the axis and apical hook formation in dicot seedlings. 

(d) Cytokinin promotes rapid internode/petiole elongation in deep water rice plants.

Choose the incorrect statement .

(a),(c) and (d)

The correct answer is Option (4) -(a),(c) and (d)

The incorrect statements are :

(a) Kinetin occur naturally in plants .

(c) Influences of ABA on plants include horizontal growth of seedlings, swelling of the axis and apical hook formation in dicot seedlings. 

(d) Cytokinin promotes rapid internode/petiole elongation in deep water rice plants.

Ethylene is a simple gaseous PGR. It is synthesised in large amounts by tissues undergoing senescence and ripening fruits. Influences of ethylene on plants include horizontal growth of seedlings, swelling of the axis and apical hook formation in dicot seedlings .Ethylene breaks seed and bud dormancy, initiates germination in peanut seeds, sprouting of potato tubers. Ethylene promotes rapid internode/petiole elongation in deep water rice plants. It helps leaves/ upper parts of the shoot to remain above water. Ethylene also promotes root growth and root hair formation, thus helping the plants to increase their absorption surface. 

Cytokinins have specific effects on cytokinesis, and were discovered as kinetin (a modified form of adenine, a purine) from the autoclaved herring sperm DNA. Kinetin does not occur naturally in plants. Search for natural substances with cytokinin-like activities led to the isolation of zeatin from corn-kernels and coconut milk. Since the discovery of zeatin, several naturally occurring cytokinins, and some synthetic compounds with cell division promoting activity, have been identified.Cytokinins help overcome the apical dominance.