Oligosaccharides from Phytophthora infestans enhance the elicitation of sesquiterpenoid stress metabolites by arachidonic acid in potato
Abstract
Poly and oligosaccharides isolated from the mycelium of Phytophthora infestans enhanced the elicitation of sesquiterpenoid stress metabolites by AA in potato tubers. One fraction markedly enhanced the elicitation activity of AA and suppressed the elicitation activity of an incompatible and compatible race of the fungus. The saccharides were partially characterized as branched chain β-linked glucans. Of 18 unsaturated and saturated fatty acids tested, only ricinoleic acid enhanced the elicitation by arachidonic acid. Of 12 sugars tested only N, N′-diacetyl-d-chitobiose and stachyose enhanced elicitor activity of AA. The two sugars also suppressed elicitor activity to race 4 of P. infestans. The activity of these compounds was considerably less than that of fungal glucans. Of the acids and sugars tested, only AA elicited accumulation of sesquiterpenoids. Malto-oligosaccharides isolated from Karo syrup did not affect elicitation activity by arachidonic acid or the fungus. © 1984.