Detection of Plasmopara halstedii in sunflower seeds: A case study using molecular testing

Plasmopara halstedii (Farl.) Berl. & De Toni causing downy mildew of sunflower is responsible for considerable economic losses worldwide. Because P. can be seed-transmitted, monitoring seeds pathogen contamination important the seed trade. The relevance asymptomatic or latent infections as factors disease spread have not been studied by molecular techniques. A marker based on a putative effector gene was used to examine pathogen’s presence in sunflowers growing near patches mildewed plants naturally infected fields. method conventional PCR highly sensitive detection DNA from whole seeds. By application this protocol, we found that all samples obtained symptomatic amplified expected fragment, whereas diagnostic identified one out 21 plants. Possible uses detect race identification are discussed.