Divinyl ether fatty acid synthesis in late blight-diseased potato leaves

We conducted a study of the patterns and dynamics of oxidized fatty acid de rivatives (oxylipins) in potato leaves infected with the late-blight pathog en Phytophthora infestans. Two 18-carbon divinyl ether fatty acids, colnele ic acid and colnelenic acid, accumulated during disease development, To dat e, there are no reports that such compounds have been detected in higher pl ants. The divinyl ether fatty acids accumulate more rapidly in potato culti var Matilda (a cultivar with increased resistance to late blight) than in c ultivar Bintje, a susceptible cultivar. Colnelenic acid reached levels of u p to similar to 24 nmol (7 mu g) per g fresh weight of tissue in infected l eaves. By contrast, levels of members of the jasmonic acid family did not c hange significantly during pathogenesis. The divinyl ethers also accumulate d during the incompatible interaction of tobacco with tobacco mosaic virus. Colneleic and colnelenic acids were found to be inhibitory to P. infestans , suggesting a function in plant defense for divinyl ethers, which are unst able compounds rarely encountered in biological systems.