By which action a seed coat becomes permeable to water:

1. Scarification

2. Stratification

3. Vernalization

4. All of the above

Which of the following PGR is present in coconut milk which is used in tissue culture?

1. Cytokinin

2. Auxin

3. Gibberellin

4. Ethylene

Which pigment absorbs the red and far red light:

1. Cytochrome

2. Phytochrome

3. Carotenoids

4. Chlorophyll

Seed dormancy is due to:

Geocarpic fruit is:

1. Potato

2. Peanut

3. Onion

4. Garlic

Differentiation of shoot is controlled by:

1. High auxin : cytokinin ratio

2. High cytokinin : auxin ratio

3. High gibberellin : auxin ratio

4. High gibberellin : cytokinin ratio

Nicotiana sylvestris flowers only during long days and N. tabacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross-fertilized to produce self-fertile offspring. What is the best reason for considering N. sylvestris and N. tabacum to be separate species:

1. They cannot interbreed in nature

2. They are reproductively distinct

3. They are physiologically distinct

4. They are morphologically distinct

Coconut milk factor is:
1. An auxin
2. A gibberellin
3. Abscisic acid
4. Cytokinin

What breaks the dormancy of potato tuber:
1.  Gibberellin
2.  IAA
3.  ABA
4.  Ethylene

The hormone responsible for senescence:
1.  ABA
2.  Auxin
3.  GA
4.  Cytokinin