FORMATION AND FUNCTIONING OF CHAETOMIUM COCHLIODES / FAGOPYRUM ЕSCULENTUM ENDOPHYTIC ASSOCIATION

Abstract

Many representatives of soil saprotroph fungi can penetrate into plant tissues forming endophytic associations with a positive effect on both micro- and macroorganisms. The endophytic fungi may positive act on growth processes, immune status, and resistance of plants to stress factors. For some crops, including buckwheat, the ability to form endophytic associations with soil fungi remains unexplored. Thus the main objectives of our study were to establish the features of interaction between Chaetomium cochliodes3250 and buckwheat plants. Conventional biochemical (content of plant growth regulators, activity of succinate dehydrogenase, acid and alkaline phosphatase, exoglucanase, endoglucanase, β-glucosidase, polygalacturonase) and physicochemical (content of photosynthetic pigments) study methods were used during the work. We established the capability of C. cochliodes 3250 for growth-regulating substances synthesis. The fungus could produce indolyl 3-acetic acid, gibberellic acid, that stimulates growth and development of plants both with mediator molecules, synthesizes 2,4-epibrassinolide, cholesterol and ergosterol playing an important role in plant resistance against pathogens. We found out that C. cochliodes 3250 was capable for active synthesis of cellulase complex enzymes (exoglucanase, endoglucanase, β-glucosidase) and polygalacturonase, necessary for fungus penetration into the root tissues. Pre-sowing treatment of buckwheat seeds by fungus caused the main physiological responses of plants: an increase of total adsorption and active working surface of the roots, the length and weight of plants, the leaf area and the content of chlorophylls a and b. Thus, the ability of C. cochliodes3250 to form an efficient endophytic association with buckwheat plants been improved.