Bacterial phytopathogen Pectobacterium causes soft rot disease in several vegetable crops globally, resulting in heavy agricultural losses at both the pre and postharvest stages. The present work was carried out to screen Kimchi cabbage genetic resources conserved at the National Agrobiodiversity Center, Rural Development Administration, Korea, for resistance against the soft rot pathogen Pectobacterium carotovorum subsp. carotovorum KACC 21701 over a period of three years (from 2020 to 2022). Infection of the phytopathogen was carried out at four-leaf stage and for each accession, twenty-five plants per germplasm were infected with KACC 21701. Kimchi cabbage cultivars Wangmatbaechu, Seoulbaechu, and CR Kiyoshi were used as control. Seven-days post-infection, the Disease Index (DI) values were manually recorded from zero to four, zero matched perfectly heathy plants and four completely dead plants. The 682 accessions of Kimchi cabbage exhibited varying degrees of disease resistance to KACC 21701 and thirty accessions, exhibiting a DI≤2, were considered for replication studies. During the replication studies, four landrace germplasms (IT102883, IT120036, IT120044, and IT120048) and one cultivar (IT187919) were confirmed to be moderately susceptible to KACC 21701. Results of the preliminary screening as well as replication studies were documented for the all the 682 germplasms. Addition of such information to the passport data of stored germplasms might serve as potential bio-resource for future breeders and researchers to develop resistant varieties or study the mechanisms involved in resistance of plants to such phytopathogen.

Background : To select plant resources of the possibility of development as a natural antioxidant, the antioxidant activities including total polyphenol content (TPC), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picryl-hydrazil (DPPH), ferric reducing antioxidant power (FRAP) and reducing power (RP) of perilla accessions collected from South Korea were conducted. Method and Results : A total of 18 perilla accessions by regions were selected. Two grams of dried perilla leaves were extracted with 85% ethanol and used for analysis of antioxidant activity. Antioxidant activity value was measured in a spectrophotometer. Perilla extracts showed variation in TPC ranging from 30.87 to 92.66 ㎍ GAE ㎎-1 dw. ABTS, DPPH, FRAP and RP ranged from 6.83 to 38.64 ㎍ Trolox ㎎-1 dw, 0.63 to 8.62 ㎍ ASC ㎎-1 dw, 5.05 to 17.57 ㎍ ASC ㎎-1 dw, and 4.52 to 35.69 ㎍ ASC ㎎-1 dw, respectively. TPC was high in perilla leaves of Gyeongsang-do, but other antioxidant activities were high in perilla leaves of Chungcheong-do. Cluster analysis based on antioxidant acitivities of 18 perilla accessions consist of group Ⅰ (3 accessions), Ⅱ (2 accessions), Ⅲ (5 accessions) and Ⅳ (8 accessions). Group Ⅱ characterized as higher antioxidant activities than other groups. Principal component analysis (PCA) based on antioxidant data revealed that the first two principal components (PC1 and PC2) together explained 97.78 % total variation. Conclusion : IT242410 and IT235354 of group Ⅱ showed high antioxidant activity. These resources will be useful for developing natural antioxidants.

본 연구는 농업유전자원센터에 보존 되어있는 콩 유전자원 중 한국 재래종 자원 880점을 대상으로 농업적 특성을 조사하고, 분자마커를 이용하여 유전적 다양성을 분석하였으며 결 과는 다음과 같다. 1. 개화일수는 51∼104일, 평균 74.4일이었으며 성숙일수는 28∼106일, 평균 72.2일이었고 생육일수는 101∼188일, 평균 146.6일이었다. 지역별 평균 개화일수는 강원지역이 69.5일로 가장 짧고, 제주지역이 77.9일로 가장 길었다. 또한 평균 생육일수는 강원지역이 평균 140.6일로 가장 짧고, 제주지역이 152.8일로 가장 긴 것으로 나타났다. 대조품종의 생육일수는 태광콩 133일, 대원콩 143일, 일품검정콩 129일, 풍산나물콩 146일과 비교하였을 때 중만생종인 태광콩보다 생육일수가 길어 우리나라 재래종에 만생종이 많음을 알 수 있었다. 2. 100립중의 범위는 4.3∼46.4 g이며, 평균 26.1 g이고, 립중별 분포는 대립종의 비율이 39.2%로 가장 많고, 중립종 30.8%, 극대립종 17.5%, 소립종 8.8%, 극소립종 3.8% 순으로 중립종 이상의 비율이 87.5%로 대부분이었다. 3. 종피색은 검정색의 비율이 52.4%로 가장 많았고, 황색 28.5% 순이었다. 지역별로는 경남지역 수집자원은 황색종피 비율이 높고, 제주지역은 황색, 녹색, 검정색의 비율이 유사하였으며, 경기지역은 녹색종피의 비율이 28.8%로 황색종피보다 많았다. 4. 검정콩 460점을 대상으로 자엽색 조사 결과 황색이 59.7%, 녹색이 40.1%이었다. 자엽색의 지역별 분포는 매우 커서 제주와 경남지역은 녹색 자엽비율이 각각 83.3%와 62.7%로 황색 자엽보다 월등히 많았으며, 전북과 전남지역의 녹색자엽 비율은 각각 5.7%와 13.8%로 극히 낮아 지역별 차이를 보였다. 5. 기초특성 평가 자원중 350점에 대해 7개의 SSR 마커를 이용하여 프로파일링한 결과 총 110개의 대립인자(allele)가 확인되었으며 각 유전자좌별로 대립인자수는 10개에서 26개 평균 15.7개였다. 유전적 다양성(PIC)은 0.711로 비교적 높았으며, 각 유전자좌별 allele의 수는 경북지역이 9.7로 가장 많고, 유전적 다양성은 제주가 0.693으로 가장 높았다.

This study is to raise the utilization of genetic resource of wheat (Triticum aestivum) landrace by evaluating genetic variation related to end use quality of the Far East. Allelic composition of HMW-glutenin subunits encoded by genes of Glu-1 loci associated with bread baking quality was investigated in 324 wheat landrace genetic resources originated from Korea, China, and Japan. The most frequent combination of HMW-glutenin subunits were Glu-A1c, Glu-B1b in Korean and Japanese resources, but Glu-A1a and Glu-B1c were the most in Chinese resources. By using the Glu-1 score system, 24 accessions were evaluated as 10 out of 10. As for genetic diversity, represented by polymorphic information content(PIC) index, the level of variation of Korean landrace(0.245) was lower than that in China(0.569) and Japan(0.294). When it comes to unique composition, Glu-B1f(13+16) and Glu-D1f(2+10) subunits are only in Chinese resources. Glu-B1d(6+8), Glu-B1e(20), Glu-D1b(7+8), and Glu-D1c (7+9) subunits are only in Korean resources. Consequently, this study showed that Chinese landrace collection was the most highly diverse and had distinctive characteristics compared to Korean and Japanese one. Especially, some resources having preferable genetic stock or high Glu-1 score can be valuable for wheat breeding program.