The Change of Heat Emission and Phenolic Compound Level in Hordeum vulgare (L.) and Festuca pratensis (Huds.) Calli Treated with Bipolaris sorokiniana (Sacc.) Shoem. Phytotoxins.

The presented work was conducted on calli of spring barley and meadow fescue that differed in degree of sensitivity to leaf spot pathogen Bipolaris sorokiniana. Callus reaction to fungus phytotoxins was examined on the basis of the amount of total phenolics and heat emission. The study was conducted dynamically – the measurements were performed after 1, 3, 6, 10, 24, 48, 72, 168 and 240 h after the moment when the calli were elicited with fungus metabolites. The greatest metabolic activity of fescue calli was observed between the 6th and the 24th h after treatment with phytotoxins and amounted to 170 % of control values. On the 10th day of culture this activity dramatically decreased in comparison with control (17 %). In the case of barley calli, increased heat emission was registered during the first 10 h of pathogenesis (130–150 % of control values). Calli of both studied plant species also differed in the dynamics of phenolic content changes. In meadow fescue tissue a significant decrease in phenolic level in comparison with control (40 %) was observed after the 7th day of experiment. In barley calli the amount of total phenolics decreased within the first 3 h (60–70% of control). The results obtained show that spring barley and meadow fescue differ in the rate of reaction to B. sorokiniana phytotoxins with regard to changes in metabolic activity and phenolic content. It also suggests a different degree of the plants sensitivity to the studied pathogen on tissue level. [ABSTRACT FROM AUTHOR]