Isolate-specific molecular marker development for enable detecting Korean Plasmodiophora brassicae ; the causal agents of clubroot

다국어 초록 (Multilingual Abstract)

Clubroot is one of the most economically important diseases of Brassicaceae family. This disease is caused by an obligate parasite, Plasmodiophora brassicae. This pathogen is difficult to study as it is non-culturable in laboratory, its races are variable worldwide and it has high genome similarity with host plants. In Korea, there were at least five races detected those were under four pathotype groups. A recent study conducted in Korea attempted to develop molecular markers for detecting P. brassicae isolates based on ribosomal DNA polymorphism. None o f those markers were either race-specific or pathotype-specific. This study was planned to develop isolate-specific markers by exploiting genomic sequence variations. A total of 119 markers were developed based on unique variation exists in genomic sequences of each of the races. Only 12 markers were able to detect P. brassicae strains under each isolates/races/pathotypes. Ycheon9 and Ycheon10 markers were specific to Yeoncheon isolate (race 2, pathotype 3), Ycheon14 markers was specific to race 2-isolates Yeoncheon and Hoengseong, ZJ1-3, ZJ1-4 and ZJ1-5 markers were specific to Haenam2 (race 4) isolate, ZJ1-35, ZJ1-40, ZJ1-41 and ZJ1-49 markers were specific to Hoengseong isolate and ZJ1-56 and ZJ1-64 markers were specific to Pyeongchang isolate (race 4, pathotype 3). The PCR based SCAR markers developed in this study are able to detect five Korean isolates of P. brassicae. These markers can be utilized in identifying Korean P. brassicae isolates from different regions. Additional effort is required to develop isolate specific markers for remaining Korean isolates.

목차 (Table of Contents)

• Ⅰ. Introduction 1
• Ⅱ. Materials and methods 4
• Ⅲ. Results and discussion 11
• Ⅳ. References 27
• Appendix 1 32
• 감사의 글 39