Horticultural Science and Technology 원예과학기술지 ISSN:1226-8763(Print) 2465-8588(Online)

Resistant cultivars have been developed as a response to clubroot disease, which poses a challenge to Kimchi cabbage cultivation in Korea. However, the recent problem of disease vulnerability in resistant varieties has led to collective efforts to promote genetically diverse resistant sources. The National Institute of Horticultural & Herbal Science (NIHHS, Vegetable Research Division) promotes and conserves resistant resources, and despite using the molecular markers reported thus far in analyzing the resources, a need for novel molecular markers has become apparent owing to the large number of resources that could not be amplified. To address this problem, 96 resources for resistance and vulnerability were selected among the ones conserved at the NIHHS, from which 20,540 SNPs were detected using genotype-by-sequencing (GBS) analysis. Subsequently, a molecular marker associated with resistance to the Yeoncheon strain that causes clubroot disease was developed using a genome-wide association study (GWAS). The corresponding gene had an SNP (G↔T) at the 23098380 position of A07, which was used to develop the CAPS marker that can differentiate resistance and susceptibility to the Yeoncheon strain causing clubroot disease. The gene at the position of the CAPS marker was found to be an associated gene within 21 kb, encoding a glucose-methanol-choline (GMC) oxidoreductase family protein with four V-type H⁺-transporting ATPase subunit Gs. In this study, a molecular marker specific for the Yeoncheon strain was developed. Its use, alongside other previously developed markers in selecting resistance resources, is expected to prove useful in the selection of a wide array of disease-resistant breeding sources. Furthermore, the resulting GBS data could be used for future analysis of the resistance genes associated with various strains causing clubroot disease.