Plant disease | 2021
Rapid detection of red rot disease pathogens (Pythium chondricola/P. porphyrae) in Pyropia yezoensis (Rhodophyta) using PCR-RFLP method.
Abstract
Red rot disease is one of the most well-known algal diseases infecting red algae Pyropia species. This disease seriously decreases the quality and quantity of Pyropia aquaculture products in Korea, Japan, and China. Recently we first found that Pythium chondricola (Oomycetes) infecting blades of Pyropia yezoensis. Therefore two Pythium species (P. chondricola/P. porphyrae) have been reported as red rot disease pathogens. In this study, we developed a species-specific molecular marker for discriminating the two red rot disease pathogens. Using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method based on the mitochondrial cytochrome c oxidase subunit 2 (cox2) and nuclear ribosomal RNA large subunit (LSU) regions, these two Pythium species were successfully classified without a sequencing step. This new method showed high specificity and efficiency for detecting red rot disease pathogens at the species level for both of the cultured samples and field samples. Therefore the molecular markers developed in this study are effective for long-term monitoring on the infection and distribution pattern of each Pythium species in Pyropia aquaculture farms. Moreover, the molecular monitoring can provide useful information for predicting infection and preventing mass mortality of Pyropia species by red rot disease.