Auxin was first isolated from:
1. | Coconut milk | 2. | Barley endosperm |
3. | Oat coleoptiles | 4. | Human urine |
Auxin does not:
1. Help to initiate rooting in stem cuttings
2. Promote female flowers in cucumbers
3. Prevent fruit and leaf drop in early stages
4. Promote abscission of older mature leaves and fruits
To extend their market period, fruits can be left on trees longer by the application of:
1. | Auxin | 2. | Gibberellins |
3. | Cytokinin | 4. | ABA |
Kinetin was first discovered from:
1. | Herring sperm DNA | 2. | Coconut milk |
3. | Yeast extract | 4. | Corn kernels |
Cytokinins do not help in:
1. Production of new leaves
2. Lateral shoot growth
3. Adventitious shoot formation
4. Promotion of apical dominance
Cytokinins help in delay of leaf senescence because they:
1. | Promote new leaves formation |
2. | Help overcome apical dominance |
3. | Help in chloroplast formation in leaves |
4. | Promote nutrient mobilization |
Normally, when the seeds are mature, ethylene production increases and builds-up within the fruit, resulting in a climactic event that means:
1. | A sudden spurt of growth | 2. | Leaf expansion |
3. | Rise in respiratory rate | 4. | Death of radicle |
Which PGR is used to initiate flowering and for synchronizing fruit set in pineapple?
1. | Cytokinin | 2. | ABA |
3. | Ethylene | 4. | GA |
Which PGR stimulates the closure of stomata in the epidermis and increases the tolerance of plants to various kinds of stress?
1. | Cytokinin | 2. | Giberrellin |
3. | ABA | 4. | Ethylene |
In most situations, which PGR acts as an antagonist to GAs?
1. | ABA | 2. | Ethylene |
3. | Cytokinin | 4. | Giberrellin |