ВЛИЯНИЕ ФИТОГОРМОНОВ НА РОСТ КОЛОНИЙ И СТЕПЕНЬ СПОРУЛЯЦИИ РАЗЛИЧНЫХ ИЗОЛЯТОВ ПАТОГЕНА STAGONOSPORA NODORUM

Abstract

Currently, the phytohormones cytokinins (CK) and abscisic acid (ABA) are considered as important regulators of the interaction between pathogens and plants. However, data on the role of these phytohormones in pathogenesis are contradictory, and information on the role of CK and ABA in the regulation of fungal growth and development is very limited. In this work, we studied the effects of CK and ABA on the growth of colonies and the degree of sporulation of various isolates of the pathogen Stagonospora nodorum SnB, Sn9MH-3A, and Sn4VD. The choice of phytohormone concentrations was carried out using the S. nodorum SnB isolate, and it was shown that the concentration of both CK and ABA, 0.1 µM, had the greatest effect on the sporulation of the fungus and inhibited the radial growth of the mycelium least of all. The addition of CK or ABA to the cultivation medium inhibited the growth of mycelium, but increased the sporulation of aggressive isolates of S. nodorum SnB and Sn9MH-3A. Moreover, the degree of influence of ABA on the sporulation of these isolates differed. The avirulent Sn4VD isolate increased its radial growth in the presence of the phytohormones CK and ABA, but did not begin to sporulate. Thus, the effect of CK and ABA on the growth of colonies and the degree of sporulation of the pathogen S. nodorum may be opposite and depend both on the concentration of phytohormones and on the genotype of the pathogen strain.