Question

Some blue-green algae can be used as biofertilizer as they are
 A .Photosynthesis
 B .Surrounded by mucilage
 C .Growing everywhere
 D .Capable of fixing nitrogen

Answer 1

Hint: A biofertilizer (likewise bio-compost) is a substance that contains living miniature creatures that, when applied to seeds, plant surfaces, or soil, colonize the rhizosphere or the inside of the plant and advances development by expanding the gracefully or accessibility of essential supplements to the host plant.

Complete answer:
Some blue-green growth like Anabaena and Nostoc can fix the climatic nitrogen. They are free-living nitrogen-fixing microorganisms. Consequently, they are utilized as biofertilizers in the field of rice. The climatic nitrogen isn't accessible to plants. There are some nitrogen-fixing microbes that change over barometrical nitrogen into alkali which is promptly accessible to plants.

Additional Information: Biofertilizers add supplements through the common cycles of nitrogen obsession, solubilizing phosphorus, and invigorating plant development through the amalgamation of development advancing substances. The microorganisms in biofertilizers re-establish the dirt's characteristic supplement cycle and assemble soil natural issues. Using bio-fertilizers, sound plants can be developed, while upgrading the supportability and the strength of the dirt. Biofertilizers can be relied upon to decrease the utilization of engineered composts and pesticides, yet they are not yet ready to supplant their utilization. Since they assume a few jobs, a favored logical term for such valuable microscopic organisms is "plant-development advancing rhizobacteria" (PGPR).
So, the correct answer is ‘Capable of fixing nitrogen’.

Note: Biofertilizers give "eco-accommodating" natural agro-input. Biofertilizers, for example, Rhizobium, Azotobacter, Azospirillum, and blue-green growth (BGA) have been being used quite a while. Rhizobium inoculants are utilized for leguminous yields. Azotobacter can be utilized with crops like wheat, maize, mustard, cotton, potato, and other vegetable harvests. Azospirillum vaccinations are suggested primarily for sorghum, millets, maize, sugarcane, and wheat. Blue-green growth having a place with an overall cyanobacteria class, Nostoc or Anabaena or Tolypothrix or Aulosira, fix air nitrogen and are utilized as immunizations for paddy crop become both under upland and marsh conditions.