본 연구는 지역별로 수집한 유채 균핵병 균주에 대해 등록 된 3종의 약제를 사용하여 저항성 검정을 실시하였고, 저항성 발생 가능성이 있는 약제의 작용 기작과 관련한 유전자를 분석하여 변이 유무를 확인하였다. 1. Carbendazim-diethofencarb 약제배지의 경우, 0.1 ppm 농도에서 균사 생장 억제율은 13.3~41.9% 범위로 나타났으며, 1 ppm 이상의 농도에서는 모든 균주에서 96.1% 억제율을 보여 균주의 저항성이 확인되지 않았다. 2. Fludioxonil 약제배지는 0.1 ppm 농도에서 균사의 생장이 94.2% 이상 억제되었으며, 1 ppm 농도에서부터 100%의 억제 율을 보여 가장 약제 효과가 우수한 것으로 나타나 수집한 모든 균주에서 약제의 감수성을 확인하였다. 3. Boscalid 약제배지는 앞선 2종의 약제에 비해 균주의 균사 생장 억제가 뚜렷하지 않았다. 특히 10 ppm 농도에서 무안 수집 균주는 93.9%, 나주 수집 균주는 79.3%로 지역 간 차이가 있었으며, 1000 ppm의 높은 약제 농도에서도 균사의 생장을 100%까지 억제하지 못해 약제에 대한 균주의 저항성 발생 가능성을 추측하였다. 4. 3종의 시험 약제 농도별 균핵병 균주의 균사 생장을 50% 억제하는 농도(EC50)를 분석한 결과, Fludioxonil, Carbendazim-diethofencarb, Boscalid 약제순이었으며, 그 값은 각각 0.06, 0.16, 0.43 ppm으로 나타났다. 5. 또한, 3종의 시험 약제 농도별 발생한 균주의 균핵 형성 능력은 1 ppm 농도에서 Carbendazim-diethofencarb는 5.6개, Fludioxonil은 0개로 나타난 반면, Boscalid는 최대 11.3개의 균핵이 형성되어 차이를 확인할 수 있었다. 6. Boscalid 약제에 대한 균주의 저항성을 확인하기 위해 해당 약제의 작용 기작인 SDHI와 관련된 유전자 SdhB를 염기 서열 분석하였다. 염기서열 분석 결과 무안 및 부산에서 수집 한 균주의 경우 SdhB 표준 염기서열과 일치하여 감수성이었으나, 나주, 당진, 제주, 영암에서 수집한 균주는 32번째 염기 가 C→T로 치환되어 GCA(Alanine)→GTA(Valine) 점 돌연변이를 확인하였다.
Sclerotinia rot, caused by Sclerotinia sclerotiorum, is a devastating disease that poses a serious threat to perilla production in Korea. Identifying effective sources of resistance offers long term prospects for improving management of this disease. Screening disease resistant genetic resources is important for development of disease-resistant, new cultivars and conduct related research. In the present study, perilla germplasm were screened in vitro against S. sclerotiorum using detached leaf method. Among 544 perilla accessions, two were highly resistant (IT226504, IT226533), five were resistant (IT226561, IT226532, IT226526, IT226441, and IT226589), five were moderately resistant (IT226525, IT226640, IT226568, IT220624, and IT178655), 16 were moderately susceptible, 31 were susceptible, and 485 were highly susceptible. The resistant accessions in this study could serve as resistance donor in the breeding of Sclerotinia rot resistance or subjected to selection procedure of varietal development for direct use by breeders, farmers, researchers, and end consumers.
To develop environment-friendly agricultural products with anti-microbial activity against Sclerotinia sclerotiorum as a pathogen of sclerotium disease, Aristolochia tagala Champ. was extracted by methanol and its extract was fractionated into several solvent fractions. The chloroform fraction, which showed the highest antimicrobial activity, was separated by column chromatography and obtained forty three subfractions. The forty three fractions were searched the anti-fungal activities by bioassay. The most active No. 26 subfraction was analyzed by GC-MS. Each mass spectra, corresponding to each peak of chromatogram, was compared to MS database of Wiley library. As a result, 2,4-di-tetra-butyl-phenol, 2-mono-palmitin, 1-mono-stearin were profiled as maine compounds in No. 26 subfraction. Bioassay using commercial 1-mono-stearin to test for the anti-microbial activity conformed the antimicrobial active compound. In conclusion, 1-mono-stearin identified from Aristolochia tagala Champ. was antimicrobial chemical against Sclerotinia sclerotiorum.
To develop environment-friendly agricultural products with anti-microbial activity against Sclerotinia sclerotiorum as a pathogen of sclerotium disease, Usnea longissima was extracted by methanol and its extract was fractionated into several solvent fractions. The chloroform fraction, which showed the highest antimicrobial activity, was separated by silica gel-column chromatography and obtained into nine group subfractions. The nine group fractions were searched the antifungal activities by bioassay. The most active No. 3 subfraction was analyzed by GC-MS. Each mass spectra, corresponding to each peak of chromatogram, was compared to database of Wiley library. As a result, Usnic acid was identified as main compounds. In conclusion, Usnic acid isolated from Usnea longissima was antimicrobial chemical against Sclerotinia sclerotiorum as a pathogen of sclerotium disease.
This study was conducted to evaluate the control effect of fungicides of sclerotinia rot control, growth characteristics, and seed yield in the cultivation of rapeseed. All fungicides treated had no effect on the growth of rapeseed. The major fungicides were mancozeb 75% WP, chlorothalonil 75% WP, dithianon 43% WP. difenoconazole 10% WP, benomyl 50% WP, and propineb 70% WP. Dry seed yield and control were increased largely with chlorothalonil 75% WP (33g/12l), fungicide than the other fungicides Sclerotinia rot. All fungicides had no injury with standard dosage. On the other hand all fungicides had slight injury in the double dosage level for the rapeseed.