Types of Bio Fertilizers

There are many eco-friendly fertilizer options available.fertile farmland valley image by Yali Shi from Fotolia.com

Biofertilizers are formulations of live microorganisms which are beneficial to certain plants and crops. They are applied by several methods--including to seeds, roots or soil. Most types function by increasing the availability of essential nutrients to their host plant in a form that it can easily make use of in trade for energy from the plant. Biofertilizers are more environmentally friendly than conventional petroleum-based fertilizers. The benefits of these microorganisms are a 20 to 30 percent increase in crop yield, stimulated plant growth, natural soil fertility and protection against drought as well as some soil-borne diseases.

Rhizobuim

Rhizobium is a species of bacteria. It is the most common symbiotic nitrogen fixer in the world. These bacteria aid plants by providing them with a constant source of easy-to-metabolize nitrogen at the root level. Nitrogen is an essential element to all living things. The earth's atmosphere is about 90 percent nitrogen, although it must go though the process of nitrogen fixation before plants can utilize it. Rhizobium inhabits the roots of leguminous host plants, forming lumps called nodules in which the nitrogen fixation occurs. In return, the host plant supplies nutrients and energy to the bacteria node. According to microbiology online, approximately 90 percent of legume crops are compatible for this relationship.

The name green manure can be somewhat misleading as it does not involve animal waste, but rather sowing living plant material into the soil in order to make the nutrients available upon decomposition. The most effective green manures utilize tender young plants so that they will quickly and fully decompose into the soil. Good green manures also come from leguminous plants because they have the ability to fix nitrogen and contribute it back into the soil. Ploughing is the best method for incorporating these fertilizers into the soil. Using green manure can increase crop yield by 10 to 20 percent.

Vesicular-arbucular mychorrhizae are fungi which can increase plant growth by enhancing accumulation of nutrients like phosphorous, zinc, copper and sulphur available to the host plant. The fungus forms arbuscules, an intimate point of contact between the roots of the plant and the fungi. These specialized cells transfer nutrients to the plant and energy to the fungi. These organisms can survive in a large variety of conditions, ranging from aquatic to desert. These organisms are believed to be present in almost all terrestrial plants. Studies implicate mychorrhizae formation with drought and disease resistance, increased resistance to pest damage and nematode infection, increase in production of seeds, and production of more fit offspring.