Characteristics of Antagonistic Activity of Two Trichoderma Species New to Kazakhstan Against Soil Pathogens

The high efficiency of representatives of the Trichoderma genus in suppressing a wide range of plant pathogens contributes to the conduct of large-scale research on the search for local strains. The purpose of this study is to characterize the antagonistic activity of two Trichoderma species new to Kazakhstan (T. pararogersonii and T. rossicum) isolated from the rhizosphere of Picea schrenkiana Fisch. et C.A. Mey. and Malus sieversii (Ledeb.) M. Roem. against soil phytopathogens. Identification was carried out based on analysis of its region sequences and determination of antagonistic activity was performed by the dual culture method. In the course of our study, we obtained descriptions of colonies of T. pararogersonii and T. rossicum based on isolated pure cultures, morphological data of both species, the sequence of nucleotides, information about inhibitory activity against some phytopathogens and the effect on the growth of some legumes. T. pararogersonii isolate is characterized by a weak level of inhibitory activity. When simultaneously seeded with most test objects, the radius of the colonies of the latter is the same or greater than the radius of the colonies of the Trichoderma. When using the paper disk method, a significant zone of suppression of the growth of phytopathogenic fungi by T. pararogersonii extract was noted in the variant with Alternaria spoon day 4 (23.55±0.72 mm) and the most insignificant one was noted with Purpureocillium lilacinum (Thom) Luangsa-ard, Houbraken, Hywel-Jones & Samson. T. rossicum was characterized by a higher level of inhibitory activity. It was found that with simultaneous seeding of Trichoderma and test objects on Petri dishes, the rapid growth of T. rossicum was observed in all variants of the experiment, except for the variant with Aspergillus niger Tiegh, where suppression of Trichoderma sporulation was also observed.