Name the plant growth regulator which upon spraying on sugarcane crop, increases the length of stem, thus increasing the yield of sugarcane crop.

1. Gibberellin

2. Ethylene

3. Abscisic acid

4. Cytokinin

Which of the following is  not an inhibitory substance governing seed dormancy?

1. Abscisic acid

2. Phenolic acid

3. Para-ascorbic acid

4. Gibberellic acid

Who coined the term 'Kinetin'?

1. Skoog and Miller

2. Darwin

3. Went

4. Kurosawa

Inhibitory substances in dormant seeds cannot be removed by subjecting seeds to:
1. Gibberellic acid
2. Nitrate
3. Ascorbic acid
4. Chilling conditions

Match the following concerning the activity/function and the phytohormone involved :-

(a) Fruit ripener         (i) Abscisic acid

(b) Herbicide             (ii) GA 3

(c) Bolting agent       (iii) 2, 4-D

(d) Stress hormone   (iv) Ethephon

Select the correct option from following :-

1. (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i)

2. (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)

3. (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)

4. (a)-(iv), (b)-(ii), (c)-(i), (d)-(iii)

In order to increase the yield of sugarcane crop, which of the following plant growth regulators should be sprayed ?

1. Ethylene

2. Auxins

3. Gibberellins

4. Cytokinins

Removal of shoot tips is a very useful technique to boost the production of tea- leaves. This is because

1. Gibberellins prevent bolting and are inactivated.

2. Auxins prevent leaf drop at early stages.

3. Effect of auxins is removed and growth of lateral buds is enhanced.

4. Gibberellins delay senescence of leaves.

Vernalisation stimulates flowering in -
1. Turmeric
2. Carrot
3. Ginger
4. Zaminkand

Which one of the following generally acts as an antagonist to gibberellins ?
1.  Ethylene
2.  ABA
3.  IAA
4.  Zeatin

One of the commonly used plant growth hormone in tea plantations is -

1. Abscisic acid

2. Zeatin

3. Indole-3- acetic acid

4. Ethylene