• The Plant Pathology Journal
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• 제29권4호
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• pp.451-453
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• 2013

Common root rot caused by Cochliobolus sativus is a serious disease of barley. A simple and reliable method for assessing this disease would enhance our capacity in identifying resistance sources and developing resistant barley cultivars. In searching for such a method, a conidial suspension of C. sativus was dropped onto sterilized elongated subcrown internodes and incubated in sandwich filter paper using polyethylene transparent envelopes. Initial disease symptoms were easily detected after 48h of inoculation. Highly significant correlation coefficients were found in each experiment (A, B and C) between sandwich filter paper and seedling assays, indicating that this testing procedure was reliable. The method presented facilitates a rapid pre-selection under uniform conditions which is of importance from a breeder's point of view.

• 한국균학회지
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• 제47권4호
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• pp.407-416
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• 2019

A common post-harvest disease of sweetpotato tuber is root rot caused by Fusarium solani in Korea as well as the other countries. Storage root rot disease was monitored earlier on sweetpotato (Ipomoea batatas) in storehouses of different locations in Korea. In the present study, an isolate SPL16124 was choosen and collected from Sweetpotato Research Lab., Bioenergy Crop Research Institute, NICS, Muan, Korea, and confirmed the identification as Fusarium solani by conidial and molecular phylogenetic analysis (internal transcribed spacer ITS and translation elongation factor EF 1-α gene sequences). The isolate was cultured on potato dextrose agar, and conidiation was induced. The fungus was screened for Fusarium root rot on tuber of 14 different varieties. Among the tested variety, Yenjami, Singeonmi, Daeyumi, and Sinjami showed resistant to root rot disease. Additionally, the pathogen was tested for pathogenicity on stalks of these varieties. No symptom was observed on the stalk, and it was confirmed that the disease is tissue specific.

• 한국식물병리학회지
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• 제14권6호
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• pp.594-597
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• 1998

The optimal quantity of inoculum was determined to screen resistance of garlic cultivars against Sclerotium cepivorum and 30 cultivars was tested. The growth of the pathogen in detached roots, Disease incidence was increased when the inoculum density was raised form 10 to 100 sclerotia. The optimal inoculum density to differentiate resistance or susceptibility of garlic cultivars was seemed to be 50 sclerotia. The cultivars collected from England, Japan, Nepal and Turkey, and cultivars such as common red, PI1356104 and PI135693 were less than the other cultivars in their disease incidence. The growth of S. cepivorum in detached roots varied from 23 to 33 mm according to garlic cultivars. There was no relationship between the disease incidence and the growth in detached roots. The sclerotial germination was increased significantly when root extract was extract was added. The addition of only distilled water resulted in 13% germination, but the addition of 0.25 g of root extract in 100 ml distilled water resulted in more than 85% germination. There was no difference in the stimulation of sclerotial germination among cultivars which showed different resistance.

• Journal of Ginseng Research
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• 제26권3호
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• pp.151-158
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• 2002

Ginseng (Panax quinquefolius L.) has become one of the most valuable herb crops grown in North America. However, traditional cropping practices are favourable to disease and significant losses due to root disease are common, despite frequent use of fungicides. Seedlots are often contaminated with pathogens, however, little is known about the causes of seed decay and the role of seed pathogens as incitants of root rots. It was shown that both Fusarium spp. and Cylindrocarpon destructans were able to rot seeds and that C. destructans was more virulent than Fusarium spp. on seedling roots. A modified rose bengal agar MRBA) medium (1 g KH$_2$PO$_4$; 0.5 g MgSO$_4$; 50 mg rose bengal; 10 g dextrose; 5 g Bacto peptone; 15 g Bacto agar; 30 mg streptomycin sulfate; 250 mg ampicillin; 10 mg rifampicin; 500mg pentachloronitrobenzene; 500 mg dicloran; and 1 L distilled water) was superior to potato dextrose agar in detecting C. destuctans in diseased roots. Isolation of C. destructans from diseased seedlings arising from seeds sown in replant soil supported the hypothesis that this pathogen is a cause of ginseng replant failure in North America.

• 식물병과 농업
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• 제5권2호
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• pp.77-83
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• 1999

In 1997 surveys 82 out of 180 crucifer fields were infected with clubroot disease in a range of 1-100% of diseased plants and among crucifier crops Chinese cabbage was the most severe, In cropping systems Chinese cabbage-monocropping of Chinese cabbage-radish were found to be most common in major Chinese cabbage production areas. Welsh onion squash or paddy rice were also planted between cropping of Chinese cabbage. Paddy fields converted to upland were lowered in incidence of clubroot disease and fields with loam to silty loam soil were more severe in disease than those with sandy soil. Soil pH and organic contents were nor related to clubroot disease severity. Soil fauua such as total fungi bacteria actinomyces Pseudomonads and Bascillus were not correlated with severity of the disease. Root rall development on Chinese cabbage seedlings was initifially observed under a microscope 13 days after inoculation with Plasmodiophora brassicae but 18 days by naked eyes after inoculation. Root galls were formed mostly around collar roots and gradually spread to main root lateral roots and secondary root branches. Root galls started to enlarge greatly in size and weight from 23 days after inoculation. Chinese cabbage plants at mid-growth stage with root gall development were reduced to 1/2 of that of healthy plants in number of leaves 1/4-1/5 in above ground fresh weight 1/6 in root length but increased to 3 times in diameter of collar root. Diseased plants had little root hairs. Diseased Chinese cabbage plants at harvest were reduced by 9,1-11.8% in head weight compared to healthy plants a positive correlation was observed between root and head weight but those relationships were rot found in the diseased plants.

• 한국식물병리학회지
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• 제14권6호
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• pp.668-675
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• 1998

강원 고랭지의 대표적 지대인 평창의 대관령, 홍천의 내면 그리고 횡성의 둔내지역에서 재배되고 있는 주요 원예작물에 대해 1994년$\sim$1997년까지 4년에 걸쳐 실시한 병해조사의 결과는 다음과 같다. 1) 배추와 무에서는 순무모자이크바이러스(TuMV)가 '92년부터 고랭지에 다발생하여 '94년과 '96년에 피해가 심하였으며, 이 바이러스병과 함께 무름병의 발생이 심한 편이었으며, 최근에는 무사마귀병의 피해고 '96년부터 점증 추세에 있으며 수년 전까지 피해가 심했던 뿌리 마름병은 최근 발생이 지극히 저조한 점이 특이하다. 거의 모든 채소작물에서 무름병, 잿빛곰팡이병, 노균병, 흰가루병, 잘록병, 검은무늬병 등의 발생이 심한 것이 특징인데 저지대와 달리 고랭지 기후환경과 무관하지 않았을 것이다. 한편 조사기간 중 새로운 미기록종으로는 셀러리의 바이러스(BBWV)와 잿빛곰팡이병(Botrytis cinerea), 메론의 점무늬병(Cercospora citullina), 딸기의 흰가루병(Erysiphe polygori), 양상추의 흰가루병(Erysiphe cichoraceaium) 등이 밝혀졌으며 기주 미기록으로는 파슬리의 무사마귀병(Plasmodiophora brassicae)이 밝혀진 것이 특이하다. 2)여러 가지 화훼작물에는 주로 바이러스병, 잿빛곰팡이병, 시들음병, 흰무늬병 등의 발생이 많았으며 특히 자생 나리류에 흰무늬병(Cercospora spp.) 발생이 심하였다. 미기록종으로는 꽃도라지의 시들음병(Fusarium oxysporum f. sp. eustomae), 바이러스병(BBWV, CMV), 균핵병(Sclerotinia sclerotiorum), 잿빛곰팡이병(B. cinerea), 카네이션의 반점병(Cladosporium echinulatum), 용담의 시들음병(Fusarium oxysporum), 잎마름병(Alternavia dianthi) 등과 Phytoplasma에 의한 스타티스의 빗자루병, 리아트리스의 빗자루병, 자생나리류의 흰무늬병(Cercospora sp.), 스토크의 TuMV 등이 동정되었다.

• The Korean Journal of Ecology
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• 제15권3호
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• pp.297-309
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• 1992

The growth of digitaria adscendens and eleusine indica, annual weeds common in japan, was experimentally analyzed under varying untrient conditions. compared with e. indica, d. adscendensshowed a higher the two under high nitrogen availability. Higher net assimilation rate(nar) in d. adscendens than e. india was responsible for high RGR in D. adscendens under the low nitrogen availability. The different of NAR in the two species was induced not by leaf nitrogen content but by nitrogen use efficiency. Under unfertilized conditions nitrogen uptake rate(nur) was greater in d. adscendens than e. indica. Specific absorption rate in two species was similar, but root mass was greater in d. adscendens than e. indica.d. adscendens allocated more dry matter to roots than e. india earlier stage of seedlings. The contributed to higher rot mass and in turn resulted in higher nur in d. adscendens than that in e. india. It is concluuded that the larger allocation of dry matter to roots at early seedling stage in d. adscendens plays an important role in obtaining nitrogen for the continuation of growth under low nitrogen availability.

• 식물병연구
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• 제12권2호
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• pp.65-68
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• 2006

장미는 세계적으로 가장 많이 재배되고 있는 화훼작물로서 최근에 양액재배 및 토양재배 되는 장미에서 발생하는 줄기마름증상에 대한 연구를 수행하였다. 장미의 가지나 줄기가 말라죽는 증상은 크게 4 가지 병에 의한 것으로 조사되었는데, Botrytis cinerea에 의한 잿빛곰팡이병, Coniothyrium fuckelii에 의한 가지 마름병, Colletotrichum gloeosporioides에 의한 탄저병, 그리고 Pythium sp. 에 의한 뿌리썩음병이었다. 이들 병의 진단과 방제에 도움이 되고자 병 증상과 병원균의 특성에 대하여 기술하였다.

• Plant Resources
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• 제1권1호
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• pp.43-48
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• 1998

The objective of this study was to determine how elevated $CO_2$ and temperature affected early growth and competition between direct seeded rice (Oryza sativa) and a common paddy weed (Echinochloa glabrascens). By using temperature gradient chambers. Rice and E. glabrescens were grown for 5 weeks at ratios of 1:0. 3:1 and 0:1 at three temperatures ($16.4^{\circ}C,\;19.8^{\circ}C,\;and\;22.2^{\circ}C$) and either in ambient (361ppm) or elevated (566ppm) $CO_2$. For both species. elevated $CO_2$ had no effect on mainstem leaf number while air temperature had a slight positive effect which was greater in E. glabrescens than rice. With elevated $CO_2$ rice leaf area index and plant height increased alightly in all species combinations but no increases were observed for E. Glabuescens. For rice in all combinations. elevated $CO_2$ tended to increase the rot and total biomass much more than any other growth parameters: the increases in root and total biomass resulting from elevated $CO_2$ ranged from 16% to 40%. depending on air temperature. At the lowest temperature, the decrease in rice biomass in combination with E. glabrescens was significantly greater at elevated $CO_2$ (18%) than ambient $CO_2$ (3%). At the highest temperature, however, the decrease in rice biomass at elevated $CO_2$ (22%) was less than that at ambient $CO_2$ (36%). The competitive ability of rice as measured by the decrease in biomass when grown in combination with E. glabrescens depended strongly on root growth and/or allocation. These results suggest that at higher temperatures elevated $CO_2$ could enhance the competitive ability of direct seeded rice during early growth. However, at lower temperatures. the competitive ability of E. glabrescens seems to be greater.

• 한국유기농업학회지
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• 제24권3호
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• pp.435-451
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• 2016

본 연구는 유기재배와 관행재배지의 토양화학성 및 인삼의 생육특성을 비교 분석하기 위하여 수행하였다. 유기재배 인삼과 관행재배 인삼 시료 채취는 전국 14개 지역 52개 포장에서 4, 5, 6년근을 대상으로 2013년부터 2015년까지 3년에 걸쳐 10월부터 11월까지 2개월 동안 이루어졌다. 인삼 유기재배에서는 수량을 높이기 위해 관행재배지와 비슷하게 양분의 함량이 높아지고 있어 토양화학성기준에 맞는 적합한 관리가 요구된다. 유기재배 인삼은 관행재배 인삼보다 생육기간이 60일 이상 짧은 특징을 보였으며 1 ha당 평균 수량도 관행 수량의 60% 수준이었다. 근중은 유기재배 인삼이 관행재배 인삼의 54% 정도였다. 동직경 및 체형계수도 유기재배 인삼이 관행재배보다 더 작아 유기재배 인삼이 가늘고 긴 특징을 보였다. 근장은 답전윤환지의 비율이 낮은 관행재배 인삼 5년근에서 길었다. 지근의 수는 직파재배의 비율이 높은 유기재배 인삼 5, 6년근에서 적었다. 건물중은 관행재배보다 조기낙엽이 발생된 유기재배 인삼의 5, 6년근에서 뚜렷하게 낮았다. 동할과 뿌리썩음병은 관행재배에서 많은 경향이었는데 동할은 4, 6년근에서 뚜렷하게 많았으며 뿌리썩음병은 5, 6년근에서 많이 발생되었다. 토양수분의 영향을 많이 받는 적변과 선충의 피해는 유기재배 4년근에서 많았다. 즉 유기재배 인삼은 관행재배보다 조기낙엽 현상이 뚜렷하여 수량 및 근중이 낮은 반면 생리장해는 적었다. 유기재배 인삼의 수량을 높이기 위해서는 조기낙엽의 문제를 극복할 수 있는 재배 기술적인 연구가 필요하며 생리장해를 줄일 수 있는 토양 수분관리가 필요하다.