Parthenocarpic tomato fruits can be produced by:

1.	removing androecium of flowers before pollen grains are released
2.	treating the plants with low concentrations of gibberellic acid and auxins
3.	raising the plants from vernalised seeds
4.	treating the plants with phenylmercuric acetate

An enzyme that can stimulate the germination of barley seeds is:

1. $\mathrm{\alpha }$-amylase

2. lipase

3. protease

4. invertase

Ethylene is related with:

1. Aerobic respiration

2. Climacteric phenomenon

3. Anaerobic respiration

4. Fermentation

It takes a very long time for pineapple plants to produce flowers. Which combination of hormones can be applied to artificially induce flowering in pineapple plants throughout the year to increase yield?

1. Cytokinin and Abscisic acid

2. Auxin and Ethylene

3. Gibberellin and Cytokinin

4. Gibberellin and Abscisic acid

What is the site of perception of photoperiod necessary for induction of flowering in plants?

1. Leaves

2. Lateral buds

3. Pulvinus

4. Shoot apex

The phytohormone which is supposed to be one of the factor responsible for regulating the opening and closing of stomata:

1. ABA

2. GA

3. IBA

4. Kinetin