The possibility of using biochar in plant protection from pathogens

Abstract

Literature review showed, that the utilization of organic amendments has been proposed to decrease the incidence of plant diseases caused by soilborne pathogens. Biochar can be effective against both soilborne pathogens (e.g. Fusarium spp., Phytophthora spp., Rhizoctonia solani) and airborne (e.g. Botrytis cinerea, different species of powdery mildew). Five different mechanisms have been pro posed to explain biochar disease suppression: (1)-induction of systemic resistance in host plants; (2)enhanced abundance and activities of beneficial microbes, including mycorrhizal fungi; (3)-modification of soil quality in terms of nutrient availability and abiotic conditions such as liming eff ECT; (4)-direct fungitoxic effect of biochar; (5)-sorption of allelopathic, phytotoxic compounds that can directly harm plant roots and thus promote pathogen attacks. Potential side-effects of biochar have been reported, like the possibility of absorbing agrochemicals like herbicides, insecticides and fungicides, thus reducing their efficacy. A lot of investigations on the mechanisms underlying biochar disease suppression, as well as long-term field experiments, are very needed to make biochar a safe, affordable and effective tool for the control of these plant pathogens.