Evidence for release of the elicitor arachidonic acid and its metabolites from sporangia of Phytophthora infestans during infection of potato

摘要: Abstract Arachidonic acid (AA), an abundant fatty in lipids of Phytophthora spp., elicits a series host defence responses potato that typically occurs following infection with incompatible races infestans. To better understand initial processing this unusual fungal elicitor during infection, we examined AA metabolism leaves their inoculation sporangia had been radiolabelled 14C-AA. Sporangia incorporated 14C-AA primarily into phospholipids, and di- tri-glycerides. Microautoradiography these revealed radioactivity was distributed throughout cytoplasm cell walls, often associated lipid bodies. In leaf tissues treated pure 14C-AA, found polar neutral fractions but not galactolipids. Analyses extracted from sampled at various times after 14C-AA-labelled similar distribution among the classes. Inoculated also were by micro-autoradiography. Radioactivity observed cells both compatible interactions, present earlier (9 h inoculation) than interaction (12 inoculation). sections including areas several layers distant site structures. These results provide direct evidence and/or its metabolites are released rapidly spores P. infestans have limited systemic movement within sites early phases leaves.