Induction of wheat defense responses against Septoria tritici agent

Abstract

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 regulator role of NO and oxalic acid in induction of wheat defense responses against Septoria tritici agent during ontogenesis. Methods. The peroxidase and ascorbateperoxidase were measured in leaves of spring wheat plants varieties Nedra and Etud upon treatment of donor NO – sodium nitroprusside – and 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 elicitors - nitric oxide (NO) and oxalic acid induce wheat two cultivars (Nedra and Etud) defense responses against leaf blotch agent Septoria tritici. Initiation of defense responses in elicitor-treated plants occurs in a short period of time. 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, NO, oxalic acid, plant defense responses.