The Effect of Biochar on Increasing Plant Resistance to Pathogens

Biochar is a coal that is prepared during the pyrolysis process by burning plant biomass and agricultural waste in the presence or absence of oxygen at a temperature around 450-550°C that is used as a fertilizer. In view of agriculture, one of the benefits of biochar is waste management in agriculture. This solid material is rich in carbon and has a large capacity to reduce greenhouse gases such as carbon dioxide and methane released from waste due to very slow decomposition rate compared to other organic materials, and can keep carbon for a thousands of years. Biochar is widely known as an efficient way for carbon sequestration and increasing soil fertility. It is used as a soil texture improver or to regenerate lands as well as protecting the environment against certain pollutants. By the addition of biochar, the stability of soil will increase the organic carbon against environmental factors and reduces mineralization which increases organic carbon and improves soil structure. Increasing water holding capacity and activity of microorganisms and better absorption of nutrients from soil is one of the main roles of biochar. In addition, biochar will improve crop yields, management of agricultural waste. Increasing plant's systemic resistance to a number of plant pathogens and uptake of pesticide and herbicide residues from the soil will cause the growth of healthier plants. Development of organic agriculture and problems that resulted in air pollution has made use of this type of fertilizer around the world, however, this organic material has remained somewhat unknown in Iran.