How can micro-organisms be used to decrease the use of chemical fertilizers and pests?

Explanation

The chemical fertilizers are very expensive and contribute significantly to pollution. Pesticides do not differentiate between target and non-target and their gradual biomagnification produces toxic effects in the organisms. In order to avoid these, the farmers are enormously using biofertilizers which enrich the nutrient quality of the soil. The biofertilizers (cyanobacteria Bacteria) are widely distributed in aquatic and terrestrial environments and they have the ability to fix atmospheric nitrogen. These biofertilizers do not pollute the environment and are specific in their action. These days, a number of biofertilizers are available commercially in the market and farmers use these regularly in their fields to replenish soil nutrients and to reduce dependence on chemical fertilizers. Similarly, biological pest control methods are being adopted to avoid the use of pesticides.
Biological pest control methods are cheap, specific in their action and these are preferred by farmers. For example, the ladybirds are useful to get rid of Aphids, the pest of vegetables and fruits.