Question
Write a short note on bio-fertilizer.###What is bio-fertilizer? Explain with example.
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Answer
Bio-fertilizers : Microbes, that increase soil fertility, are called bio-fertilizers. Several nitrogen fixing bacteria like blue-green algae, root fungi etc. increase the fertility of the soil. Some of the important example are as follows :
1. Legume-Rhizobium Symbiosis : Rhizobium species residing in root glands of legume plants provide N2 in a usable form of to the plant.
2. Azolla-Anabaena Symbiosis : Azolla is an aquatic pteritophyte which grows on the surface of the water. Along with this, blue-green algae called Anabaena lives symbiotically and provides nitrate to the plants.
3. Free-living Cyanobacteria and Bacteria : Rivilaria and Nostoc (blug-green algae) and Chlostridium and Azobacter (free living bacteria) fix atmospheric nitrogen while living freely in the soil. Now-a-days efforts are being made to transfer the nitrogen fixing gene (Nif gene) of microbes to higher plants by application of biotechnology techniques.
1. Legume-Rhizobium Symbiosis : Rhizobium species residing in root glands of legume plants provide N2 in a usable form of to the plant.
2. Azolla-Anabaena Symbiosis : Azolla is an aquatic pteritophyte which grows on the surface of the water. Along with this, blue-green algae called Anabaena lives symbiotically and provides nitrate to the plants.
3. Free-living Cyanobacteria and Bacteria : Rivilaria and Nostoc (blug-green algae) and Chlostridium and Azobacter (free living bacteria) fix atmospheric nitrogen while living freely in the soil. Now-a-days efforts are being made to transfer the nitrogen fixing gene (Nif gene) of microbes to higher plants by application of biotechnology techniques.
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