Parthenocarpy in grapes is induced by:-

1. cytokinins

2. gibberellins

3. topoisomerases

4. primase

Phytochromes play a role in 

(1) seed germination

(2) flowering 

(3) photomorphogenesis

(4) photosynthesis.

Induction of flowering by low temperature in plants is 

1. cryobiology

2. vernalization 

3. phototropism

4. pruning.

Which of the following statements is correct regarding short day plants (SDPs)?

1. They can flower in complete darkness if supplied with exogenous nutrients.

2. They are the same as long day plants.

3. They do not have a critical photoperiod.

4. All of these.

Bud dormancy is induced by:-

1. ABA

2. ethylene

3. IAA

4. gibberellic acid.

Pruning of plants promotes branching because the auxillary buds get sensitized to:-

1. ethylene

2. gibberellin

3. cytokinin

4. indole acetic acid

Phytohormones are?
(1) hormones regulating growth from seed to adulthood

(2) growth regulators synthesised by plants and influencing physiological process

(3) hormones regulating flowering

(4) hormones regulating secondary growth

Refer the given figures on photoperiodism and select the correct option.

Abscisic acid is known as the stress hormone because it

(1) breaks seed dormancy

(2) induces flowering

(3) promotes leaf fall

(4) promotes closure of stomata

Which of the following plant growth regulators (PGRs) promotes root initiation, flowering and
induced parthenocarpy?

(1) Gibberellin

(2) Auxin

(3) Cytokinin

(4) Ethylene