Участь щавлевої кислоти в індукції системної стійкості пшениці до збудника септоріозу
Aims. The usage of biological elicitors for plant defense responses against plant pathogenic fungi may initiate tolerance of plants and prevent environmental pollution. The aim of research was to investigate the effect and oxalic acid in induction of wheat defense responses against Septoria tritici agent during ontogenesis. Methods. The phenol peroxidases, catalase and ascorbateperoxidase were measured in leaves of winter wheat plants varieties Poliska 90 and Stolychna upon treatment of oxalic acid and leaf blotch infection during ontogenesis. The morphometric parameters, degree of plant lesion and yield structure were analyzed. Results. Results obtained suggest that biotic elicitor – oxalic acid induces two wheat cultivars (Stolychna and Poliska 90) defense responses against leaf blotch agent Septoria tritici. Initiation of defense responses in elicitor-treated plants occurs in a short period of time. The effect of oxalic acid treatment increased yhe activity of APO, phenol perpxidases and decresed the catalase activity. The effect of oxalic acid also increased the grain quantity in ear and plant height. Conclusions. Biochemical nature of defense responses elicitation revealed an increase activity of cytoplasmic peroxidase (CP) which induces lignin synthesis for mechanical strengthening of the cell wall. It is also shown that changes in activity of ascorbateperoxidase (APO) reflect the functioning of the photosynthetic metabolism in leaves cells mesophillous.
Key words: wheat, Septoria tritici, oxalic acid, plant defense responses, antioxidant enzymes.