The residue left after methane production from cattle dung is:
1. | burnt | 2. | buried in landfills |
3. | used as manure | 4. | used in civil construction |
Which one of the following is not a nitrogen-fixing organism?
1. | Anabaena | 2. | Nostoc |
3. | Azotobacter | 4. | Pseudomonas |
What advantage does the mycobiont get in the mycorrhizal symbiotic relationship?
1. | Adequate uptake of water |
2. | More availability of minerals like phosphorus |
3. | Availability of carbohydrates for energy |
4. | Resistance to diseases, drought, and salinity |
Match each item in Column I [Diazotroph] with the feature in Column II and select the correct answer from the codes given below:
|
Column I |
|
Column II |
A. |
Cyanobacteria |
a. |
Actinorhizal symbiont |
B. |
Frankia |
b. |
Do not form nodules |
C. |
Rhizobium |
c. |
Free-living nitrogen fixer |
D. |
Azotobacter |
d. |
Legume symbiont |
Codes
A | B | C | D | |
1. | a | b | c | d |
2. | b | a | c | d |
3. | a | b | d | c |
4. | b | a | d | c |
The diazotroph that serves as an important biofertilizer in paddy fields is:
1. | Rhizobium | 2. | Frankia |
3. | Azotobacter | 4. | Anabaena |
Statement I: | Rhizobium forms symbiotic associations and forms nodules on the roots of non-leguminous plants. |
Statement II: | Azotobacter and Azospirillum can fix atmospheric nitrogen only as symbionts. |
Statement III: | Anabaena, Nostoc and Oscillatoria are autotrophic microbes capable of fixing atmospheric nitrogen. |