Biofertilizer : The Life Of Soil

Biofertilizer is produced from natural sources. Plants and animals dead body decomposed and mixed with soil and produced biofertilizer. Cow dung and decomposed excreta urine of other animals or compost, green manure, decomposed leaf, fish meal, bone meal, oil cake etc. all are fall in the biofertilizer. Biofertilizer (jibaja sar) living materials used to increase fertility of soils. Some free-living or symbiotic bacteria and blue-green algae (Cyanobacteria) fix gaseous nitrogen as ammonia and release it increasing the fertility of soil and water. Rhizobium or Bradyrhizobium producing root nodules in legumes and Anabaena azollae living in leaf cavities of Azolla (aquatic fern) are very efficient nitrogen fixers, and contribute about 500 kg N/ha/year. Another microsymbiont with nitrogen fixing capacity is Frankia having hyphal morphology similar to that of actinomycetes and produces nodules in woody non-legumes, like Alnus, Casuarina, Myrica, etc. It produces vesicles and sporangia in both free-living and symbiotic states. Azotobacter species are free-living (mostly root associated), aerobically nitrogen fixing bacteria. Nostoc, Calothrix, Gloeotrichia, Stigonema, etc are free-living aerobically nitrogen fixing Cyanobacteria. In addition, Vesicular Arbuscular Mycorhizae (VAM fungi) are free-living soil forms that increase nutrient uptake (specially by converting organic phosphorus into inorganic phosphorus), plant growth, nodulation and nitrogen fixation in legumes. In coastal areas of some countries, seaweeds are also used as biofertilizer. However, all these life forms may be grown artificially and inoculated in the soil as biofertilizer. The nitrogen fixers releases nitrogen during their life time and also add other elements after their death and decay, essential for the growth of crops. The biofertilizer also contributes organic matter and maintains a good soil texture. Azolla contains well balanced amino acids and high amount of anthocyanine, a -carotene. These compounds also have positive effects on growth and yield of crops.

Why we use this fertilizer ?

Its needed to present 3-5% of total biofertilizer in the soil. But in our country (Bangladesh) it is present bellow than 2% for this reason crop production decreased day by day.

 Biofertilizer helps to increase soil fertility. All elements necessary for plant growth and development, present in biofertilizer and plants easily recover the deficiency of nutrients / element for its optimum growth.

 Biofertilizer helps in increasing the developing the texture and structure of the soil. It also increases the water holding capacity of sandy soil and helps it to convert into loamy soil day by day with increasing the percentage of this biofertilizer.

 Plants uptake organic elements longtime from the soil. The effect of biofertilizer present 6-18 months in the soil, after applying it and crop can uptake this fertilizer season after season.

 After applying biofertilizer, the activity of useful micro organism is increased. It also helps in the reproduction of micro organism.

 Biofertilizer helps in plant growth. Different helpful insects like earth warm, ant, termite etc. are increase very much in the soil with the application in the soil. This insect makes holes in the soil, thus the root gets extra oxygen profusely. It increases the aeration capacity of the soil.

 It increases the erosion of soil by air and water. 

 In the summer it reduces the soil temperature and in the winter it increases the soil temperature. For this reason the growth of root system not hampered in any season.

 In increase the water holding capacity of the soil, so plants get available water in any season. For this reason, the utilization of irrigation water is maximized.

 It decreased the toxicity of insecticides & chemical fertilizer. On the other hand it has no toxic effect on soil.

 It increases the quality and quantity of crop production.

  Bismark Bangali

BSC  in Agrotechnology

  Khulna University.