Q. No.A nitrogen-fixing microbe associated with Azolla in rice fields is:
1. Spirulina
2. Anabaena
3. Frankia
4. Tolypothrix
Which one of the following is an example of carrying out biological control of pests/diseases using microbes?
1. Trichoderma sp. against certain plant pathogens
2. Nucleopolyhedrovirus against white rust in Brassica
3. Bt-cotton to increase cotton yield
4. Ladybird beetle against aphids in mustard
1. Propane
2. Mustard gas
3. Marsh gas
4. Laughing gas
1. Rhizobium
2. Frankia
3. Anabaena
4. Glomus
1. Rhizobium
2. Nostoc
3. Mycorrhiza
4. Agrobacterium
1. soya meal
2. ground gram
3. molasses
4. com meal
| 1. | Clostridium | 2. | Trichoderma |
| 3. | Aspergillus | 4. | Saccharomyces |
| 1. | Azospirillum | 2. | Rhizobium |
| 3. | Nostoc | 4. | Azotobacter |
Select the correct statement from the following:
| 1. | Biogas is produced by the activity of aerobic bacteria on animal waste |
| 2. | Methanobacterium is an aerobic bacterium found in the rumen of cattle |
| 3. | Biogas, commonly called gobar gas, is pure methane |
| 4. | Activated sludge-sediment in settlement tanks of sewage treatment plant is a rich source of aerobic bacteria |
A common biocontrol agent for the control of plant diseases is:
1. Baculovirus
2. Bacillus thuringiensis
3. Glomus
4. Trichoderma
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