감자 유전자원의 더뎅이병 저항성 평가

Evaluation of Common Scab (Streptomyces scabies) Resistance of Potato Germplasm

Total 168 clones or varieties which were collected from abroad or bred in Korea were evaluated for their field resistance to common scab (Streptomyces scabies) in the test field which were highly contaminated with pathogen in order to select resistant parents for potato breeding program. From first evaluation in 2003, 64 genotypes which showed the low rates of scab incidence were screened as tentative resistant germplasm. In the following year, they were re-evaluated in the same test field with three replicated trials and intensive measurements. From the test, ‘88K77-1’ and ‘AG34265’ were selected as highly resistant (HR) genotype to the disease with 0.0~3.6% of very low severity, 6 clones including ‘AG14188’ as resistant (R) genotype with 10.0~18.0% of relatively low severity, 7 clones including ‘Hertha’ as moderately resistant (MR) genotype with 21.4~41.3% of the severity, and subsequently, 29 clones including ‘W718’ as susceptible genotype group with more than 63.3% of the severity. The disease severities of ‘Dejima’, ‘Atlantic’, and ‘Superior’ used as control varieties were 98.9%, 78.7%, and 17.0%, respectively. The different incidence rates and severities of scab were also shown by tuber skin types of the genotypes evaluated; 78.4% and 53.5% in the russetskinned group, and 95.5% and 66.1% in smooth-skinned group, respectively, but no significance was found.