Question
Microbes can be used to decrease the use of chemical fertilisers and pesticides. Explain how this can be accomplished.
✓
Answer
Today environmental polloution is a main cause of concern. The use of chemical fertilizers to fill up the increasing demand of agriculture products is the vital cause of this pollution. Biofertilizers are organisms, which increase the nutrient quality of the soil. The main source of biofertilizers are bacteria, fungi and cyanobacteria. We have read about the nodules located on the roots of leguminous plants. These nodules are formed by the symbiotic relationship of Rhizobium. These bacteria fix the atmospheric nitrogen and convert it into organic form. Plants use it as nutrients, other bacteria (eg. Azospirillum and Azotobacter) live freely in the soil can also fix the atmospheric nitrogen. Thus, N2 increases in the soil.
Fungi establish symbiotic relationship with plants. The fungal symbiont in these associations absorbs phosphorus from soil and passes it to the plant. Plants with such relationship exhibit many other benefits like resistance to root-borne pathogens, tolerance to salinity and drought and overall growth and development. Cyanobacteria are autotrophic microbes that are found widely in aquatic and terrestrial environments. Many of these can fix atmospheric nitrogen.
Only the use of biological method to control plant diseases and pests is biological control. In modern society, these problems are controlled with the help of increasing usage of chemicals, insecticides and pesticides. These chemicals are extremely poisonous and harmful for human and animals. They pollute the environment (soil, underground water) and also have harmful effects on fruits, vegetables and crops. Herbicides are used to remove weeds. These also pollute our soil.
The bacteria Bacillus thuringiensis (Bt) is used to control the butterfly catepillers. Baculoviruses are such pathogens that attack insects and arthopods. Nucleopolyhedrovirus (NPU) are considered as best for the treatment of species-specific and narrow-spectrum insecticides.
Fungi establish symbiotic relationship with plants. The fungal symbiont in these associations absorbs phosphorus from soil and passes it to the plant. Plants with such relationship exhibit many other benefits like resistance to root-borne pathogens, tolerance to salinity and drought and overall growth and development. Cyanobacteria are autotrophic microbes that are found widely in aquatic and terrestrial environments. Many of these can fix atmospheric nitrogen.
Only the use of biological method to control plant diseases and pests is biological control. In modern society, these problems are controlled with the help of increasing usage of chemicals, insecticides and pesticides. These chemicals are extremely poisonous and harmful for human and animals. They pollute the environment (soil, underground water) and also have harmful effects on fruits, vegetables and crops. Herbicides are used to remove weeds. These also pollute our soil.
The bacteria Bacillus thuringiensis (Bt) is used to control the butterfly catepillers. Baculoviruses are such pathogens that attack insects and arthopods. Nucleopolyhedrovirus (NPU) are considered as best for the treatment of species-specific and narrow-spectrum insecticides.
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