• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2021년도 춘계학술대회
• /
• pp.101-101
• /
• 2021

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 1987년도 추계 학술대회지
• /
• pp.26-27
• /
• 1987

• The Plant Pathology Journal
• /
• 제17권6호
• /
• pp.342-346
• /
• 2001

The physiological changes in sorghum (Sorghum vulgare Pers.) leaves infected with Drechslera sorghicola were investigated through five recognizable stages of disease development. Water-soaked yellowish brown spots developed two days after inoculation, turned brown with yellow halo, enlarged and coalesced at later stages of disease development. Healthy and infected leaves were analyzed for different biochemical constituents. The chlorophyll contents were decreased significantly with the progress of infection. The levels of reducing and total sugars increased while non-reducing sugars decreased to a significant extent with the progress of disease. The concentration of total phenolics, orthodihydroxy phenols, free and glycosidic phenols showed significant changes due to infection, whereas basic and acid phenols showed little or no change with disease development. Levels of phenolic compounds increased four days after inoculation and decrease thereafter, but the concentration was higher at every stage of disease development relative to healthy tissues. Polyphenol oxidase and peroxidase enzyme activities increased to varying degrees at different stages of infection. Analysis of protein fractions showed a significant increase with the progress of disease.

• 한국자원식물학회지
• /
• 제34권4호
• /
• pp.339-345
• /
• 2021

'그린베어(Greenbear)' 품종은 곰취를 모본으로 하고 한대리 곰취를 부본으로 해서 교배 육종을 하였다. 2007년부터 2016년까지 국립식량과학원 고령지농업연구소 하우스 및 노지에서 생육 및 수량 특성을 조사하고 선발을 수행하였다. '그린베어' 품종에 있어서 엽병귀 색은 자주색이고 엽병에 털이 없다. 그리고 잎 뒷면에 털이 없어 광택이 있다. 엽맥 밀도는 2등급으로 아주 넓은 편이다. 생육 특성은 초장이 67.3 cm, 엽장 16.3 cm, 엽폭 20.4 cm, 엽병장은 39.1 cm 였다. 식물체 크기는 '곰마니' 품종보다 전체적으로 작은 것으로 나타났다. 추대기는 8월 7일이었고, 개화기는 9월 6일로 '곰마니' 품종과 유사하였다. 엽수는 주당 176매로 '곰마니' 품종 139매 보다 37매나 많았다. 그리고 주당 수량도 1,936 g으로 '곰마니' 품종 1,575 g보다 23%정도 더 많았다. 잎의 경도는 25.1 kg/cm², 잎의 두께는 0.66 mm로 '곰마니' 품종과 유사한 것으로 나타났다. '그린베어' 품종의 흰가루병 저항성은 '곰마니' 품종보다는 약간 낮지만 어느정도 높은 저항성을 보였다.

• 식물병연구
• /
• 제21권3호
• /
• pp.243-249
• /
• 2015

점무늬병은 콩에서 최대 50% 정도의 수량감소가 보고된 병으로 최근 한국 콩 재배포장에서 큰 문제로 대두되고 있어 최근 6년간의 보급 품종을 대상으로 콩 점무늬병에 대한 저항성 검정을 실시하였다. 표준화된 검정방법을 적용하기 위해 가장 효과적인 포자 형성 배지 조건을 탐색하고 저항성 검정 평가 기준을 확립하였다. 포자형성은 $25^{\circ}C$, 12시간 광 조건과 암 조건에서 V8 juice를 이용한 배지의 포자 형성이 가장 효과적임을 알 수 있었다. 접종은 $10^5spores/ml$로 준비하여, 제 5 복엽 완전전개기인 V6 stage까지 키운 건강한 콩 식물체에 실시하였고 병 반응은 28일 동안 관찰하였다. 그 결과 대풍은 8개 균주 모두 저항성을 보였고, 신팔달2호는 7개 균주에, 연풍, 청아는 6개 균주에 저항성을 보였다. 반면에 황금, 태광, 대원, 천상, 신화 등은 평가한 8개 균주에 모두 감수성 반응을 나타내었다. 콩 점무늬병에 대한 저항성 품종을 육종하기 위해 표준화되고 정밀화된 저항성 검정방법과 판정 체계를 갖추는 것은 매우 중요하며 이 방법은 차후 포장 저항성 검정에도 적용할 수 있을 것이라 기대한다.

• The Plant Pathology Journal
• /
• 제36권4호
• /
• pp.305-313
• /
• 2020

Host shifting and host expansion of fungal plant pathogens increases the rate of emergence of new pathogens and the incidence of disease in various crops, which threaten global food security. Magnaporthe species cause serious disease in rice, namely rice blast disease, as well as in many alternative hosts, including wheat, barley, and millet. A severe outbreak of wheat blast due to Magnaporthe oryzae occurred recently in Bangladesh, after the fungus was introduced from South America, causing great loss of yield. This outbreak of wheat blast is of growing concern, because it might spread to adjacent wheat-producing areas. Therefore, it is important to understand the host range and population structure of M. oryzae and related species for determining the evolutionary relationships among Magnaporthe species and for managing blast disease in the field. Here, we collected isolates of M. oryzae and related species from various Poaceae species, including crops and weeds surrounding rice fields, in Korea and determined their phylogenetic relationships and host species specificity. Internal transcribed spacer-mediated phylogenetic analysis revealed that M. oryzae and related species are classified into four groups primarily including isolates from rice, crabgrass, millet and tall fescue. Based on pathogenicity assays, M. oryzae and related species can infect different Poaceae hosts and move among hosts, suggesting the potential for host shifting and host expansion in nature. These results provide important information on the diversification of M. oryzae and related species with a broad range of Poaceae as hosts in crop fields.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2022년도 추계학술대회
• /
• pp.257-257
• /
• 2022

Late blight, caused by the hemibiotrophic oomycete pathogen Phytophthora infestans, has been the most important disease limiting potato production worldwide. P. infestans undergo major population shifts in agricultural systems via the successive emergence and migration of asexual lineages. The phenotypic and genotypic bases of these selective sweeps are largely unknown but management strategies need to adapt to reflect the changing pathogen population. Here, we used molecular markers to divide the 86 South Korea isolates into six clonal lineages: KR_1_A1, KR_2_A2, SIB-1, US-11, SIB-1 like, and KR-2 like. We documented the emergence of a new lineage, termed SIB-1 like, and KR-2 like, and their rapid replacement of other lineages to exceed 35% of the pathogen population across South Korea. Genome analyses of the Korean P. infestans populations revealed extensive genetic polymorphism, particularly in effector genes. Importantly, SIB-1 like isolates carry an intact Avr8 effector gene that triggers resistance in potato carrying the corresponding R immune receptor gene R8 cloned from Solarium demissum. These findings point toward a strategy for deploying genetic resistance to mitigate the impact of the SIB-1 like lineage and illustrate how pathogen population monitoring, combined with genome analysis, informs the management of devastating disease epidemics. Further study is being done on pathogenicity of the SIB-1 like isolates on cultivated potatoes and changes in expression patterns of disease effector genes within the SIB-1 like isolates

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2020년도 춘계학술대회
• /
• pp.114-114
• /
• 2020

• The Plant Pathology Journal
• /
• 제27권4호
• /
• pp.324-332
• /
• 2011

Soil-borne barley yellow mosaic disease caused by Barley yellow mosaic virus (BaYMV) or Barley mild mosaic virus (BaMMV) gives a serious threat to the winter barley cultivated in the southern regions in Korea. It is important to develop resistant varieties for stable and high-yield production. The objectives of this study were to evaluate 22 genotypes of exotic barley germplasms carrying the resistance genes rym1 through rym12, with the exception of rym10, and to determine the genes that confer resistance to BaYMV or BaMMV in Korea. Using the traditional visual scoring of symptoms at 4 locations over 3 years, average disease rate values differed (P < 0.001) among the genotypes. ELISA test revealed the presence of both BaYMV and BaMMV in all of the field sites but Jinju and significantly different rates of infection among genotypes and years. Barley genotypes differed in how virus quantities and pathogen-induced symptoms were correlated, especially in response to BaYMV. Disease incidence was affected by the climatic conditions present during the early growing stage before overwintering. A Chinese landrace, 'Mokusekko 3', carrying rym1 and rym5 was comparatively resistant at all locations studied. The barley genotypes carrying either rym6 or rym9 were susceptible to the viral strains. The genotypes carrying rym5 were resistant in Jinju and Milyang but susceptible in Iksan and Naju. The resistance genes rym2 and rym3 were effective in local strains and would be potent contributors to disease resistance.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2021년도 추계학술대회
• /
• pp.147-147
• /
• 2021