Tag: biofertilizers

Questions Related to biofertilizers

Which of the following microorganisms is used as a biofertilizer?

  1. Bacillus

  2. Azospirillum

  3. Pseudomonas

  4. Saccharomyces


Correct Option: B

A fern commonly inoculated to paddy fields is

  1. Azolla

  2. Marsilea

  3. Salvinia

  4. Anabaena


Correct Option: A

In paddy fields, biological nitrogen fixation is chiefly brought about by.

  1. Cyanobacteria

  2. Green algae

  3. Mycorrhiza

  4. Rhizobium


Correct Option: A
Explanation:

In paddy fields,biological nitrogen fixation is brought about by Cyanobacteria(Nostoc, Anabaena).

Correct answer-A

They help in increasing soil fertility.

  1. Pseudomonas and cereals

  2. Bacillus and Penicillium

  3. Salvinia and Marsilea

  4. Nostoc and legumes


Correct Option: D
Explanation:

Nostoc and legumes help in increasing soil fertility by nitrogen fixation in the soil.

Correct answer-D

Biofertilizers include

  1. Nitrogen fixing bacteria

  2. Mycorrhiza

  3. Nitrogen fixing cyanobacteria

  4. All of the above


Correct Option: D

Some blue green algae can be used as biofertilizer as they are

  1. Photosynthesis

  2. Surrounded by mucilage

  3. Growing every where

  4. Capable of fixing nitrogen


Correct Option: D
Explanation:

Some cyanobacteria can fix atmospheric nitrogen in anaerobic conditions by means of specialized cells called heterocysts. These heterocyst forming species are specialized for nitrogen fixation, and are able to fix nitrogen gas into ammonia, nitrites, or nitrates, which can be absorbed by plants and converted to proteins and nucleic acids as nitrogen cannot be directly absorbed by plants. Therefore, some of the cyanobacterial species are used as biofertilizers. 

So, the correct answer is 'Capable of fixing nitrogen'

Which one of the following is useful in rice fields?

  1. Rhizobium

  2. Clostridium

  3. Anabaena

  4. Ferrobacterium


Correct Option: C

Which is used as biofertilizer?

  1. Azolla

  2. Marchantia

  3. Funaria

  4. Dryopteris


Correct Option: A

Biofertilizer is?

  1. Manure

  2. Enriched manure

  3. Nutrient rich organisms

  4. Composited manure


Correct Option: C
Explanation:

biofertilizer is a substance which contains nutrient rich living microorganisms which colonize the rhizosphere or the interior of the plant and promotes the growth of the plant or the seed by increasing the availability of primary nutrients to the plant.

Cyanobacteria are / Nostoc is

  1. Oxygenic with nitrogenase

  2. Oxygenic without nitrogenase

  3. Non- Oxygenic with nitrogenase

  4. Non - Oxygenic without nitrogenase


Correct Option: A
Explanation:

The cyanobacteria fix atmospheric nitrogen through the help of enzyme nitrogenase and are oxygenic photosynthetic also.

So, the correct option is 'Oxygenic with nitrogenase'.