• The Plant Pathology Journal
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• 제36권2호
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• pp.133-147
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• 2020

Hexanal, a C-6 aldehyde has been implicated to have antimicrobial properties. Hence, this study was conducted to determine the antifungal activities of hexanal vapor against major postharvest pathogens of banana viz., Colletotrichum gloeosporioides and Lasiodiplodia theobromae. The pathogens were cultured in vitro and exposed to hexanal vapor at 600, 800, 1,000 and 1,200 ppm. Mycelial growth of both fungal pathogens were inhibited completely at 800 ppm and the incidence of anthracnose and stem-end rot diseases reduced by 75.2% and 80.2%, respectively. The activities of peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase and glucanase had transiently increased in hexanal vapor treated banana by 5 to 7 days and declined thereafter. Postharvest treatment of banana with hexanal vapor resulted in phospholipase D inhibition and also resulted in cell wall thickening of the treated fruit, which impeded the penetration of the pathogenic spores. This was further confirmed by scanning electron micrographs. The defense-related protein intermediaries had increased in hexanal vapor treated banana fruit, which suggests induced resistance against C. gloeosporioides and L. theobromae, via., the phenylpropanoid pathway which plays a significant role in hindering the pathogen quiescence. Delayed ripening due to inhibition of phospholipase D enzyme, inhibition of mycelial growth and induced systemic resistance by defense enzymes collectively contributed to the postharvest disease reduction and extended shelf life of fruit.

• 한국식물병리학회지
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• 제14권5호
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• pp.452-457
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• 1998

Thirty-eight isolates of Phytophthora sp. caused rots on roots and basal stems were collected from five flowering plants from 1992 to 1997 at eight cultivation areas in Korea. All the isolates were identified as P. nicotianae based on following characteristics. The fungus produced markedly papillate, not caducous and ovoid to spherical sporangia, abundant chlamydospores, and small oospores with amphigynous antheridia only when paired with either A1 or A2 mating type. All isolates grew well at 35$^{\circ}C$ and showed distinct arachnoid colony patterns on CMA and PDA. Sizes of sporangia and chlamydospores of five representative isolates from each plant averaged 43-52$\times$30-38 ${\mu}{\textrm}{m}$ and 28 ~34 ${\mu}{\textrm}{m}$. Mating type of the isolates was either A1 or A2, and oogonia and oospores were measured as 28~31 ${\mu}{\textrm}{m}$ and 21~25 ${\mu}{\textrm}{m}$. PCR-RFLP analysis of rDNA of the five isolates resulted that restriction band patterns of the small subunit and ITS regions were identical to a perilla isolate of P. nicotianae, but distinct from P. cactorum and P. capsici. Cross inoculation tests showed that the five isolates had pathogenicity to lily, christmas cactus, anthurium, baby's breath and carnation with different degrees. However, each isolate showed stronger pathogenicity to its corresponding original host than others. Among five lily cultivars Georgia and Quririna were more susceptible than Napoli and others. This is first report of Phytophthora root and stem rot of lily, Christmas cactus, anthurium, baby's breath and monochoria in Korea.

• 농약과학회지
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• 제4권1호
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• pp.38-43
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• 2000

포도 병해충 방제기술 확립을 위한 연구의 기초단계로서 포도 재배 농가를 대상으로 병해충 방제실태 및 피해에 대한 설문조사를 실시한 결과, 방제가 가장 어려운 해충은 포도호랑하늘소와 포도유리나방이었으나, 병은 탄저병, 노균병, 흰가루병, 새눈무늬병, 갈색무늬병 등 다양하였다. 병충해의 발생은 포도 재배방식에 따라 차이가 있었으며, 해충보다는 병에 의해서, 시설재배보다는 노지비가림재배에서 감수율이 더 컸다. 농가의 병충해 식별능력은 높다고 할 수 없었으며, 병충해가 발생하면 주로 농약상이나 이웃 농가에 문의하고, 농약상이 처방해 주는 농약을 처리하는 것으로 나타났다. 방제력을 활용하는 농가는 사용하지 않는 농가보다 적었으며, 대부분의 농가가 예방차원에서 방제를 하고 있었다. 반 이상의 농가가 적어도 한가지의 농약을 영양제와 혼합처리하고 있었으며, 살충제는 5회 이내로 처리하는 반면, 살균제는 6회 이상을 처리하고 있었다. 단위 면적 당 방제비용은 변이 폭이 매우 컸다.

• Journal of Ginseng Research
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• 제20권4호
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• pp.472-500
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• 1996

Researches on mineral nutrition, physiology and phyrsiological diseases, . cultivaction methods. brceding. pest control quality management and extension during 1976-1995 in Korea were reviewed Review in brceding and pest control was restricted to the researches directely related to cultivaction. Mineral nulrient up take. partion and varicos factors such as top dreasing. Light intersity etc. and interrelationship between minerals were investigated. Top dressing was not effective due to low minera1 requorement Physiological characteristics on tempelature light and water were well elucidated and applied to assess traditional cultivation method and its inovation. Photosyrnthetic pigments. light harvest proteins and activity of related enzymes were studied. In nitrogen metabolism arginine, praline, ammonium, threonine appeared to have important role in re growth of shoot Saponin metabolism was studied in relation to growth and new ginsenosides were found but physiological role of saponin was not clearly elucidated yet Endogenous growth regulators were reported and various erogenous growth regulators were studied for growth stimulation. short stem and seed pruning etc. Various physiological diseases were investigated for cause and control measures were established. Water culture was little studied Forest culture was studied but not retched the recommendable stage Drip irrigation straw mulching. seasonal shading and soil preparation method including soil fertility adjustment were established for practical application. Shading materials completely changed to polyethylene net and materials of polymers The research on ginseng cultivation in paddy field opened the way to establish the permanent ginseng cultivation plantation Ginseng harvester and seeder were developed in the late 1950s. Transplanted and many other machines were developed in the early 1990s. In ginseng breeding only pure line selection was of practical significance several verities were at the stage of seed propagation at ginseng plantations. Mutation breeding (${\gamma}$-ray. X-ray chemicals) was not successful. The research on plantlet formation through tissue culture was a little progressed but still far behind to vegetative propagation. Disease control research was concentrated in the isolation and identification of pathogans. their ecological charactelistics and biological control and soil humigation. Potato root rot nematodes was found and control method was established. Insect and small animal control research was greatly progresses in identification, ecological investigation, and ecological and physical control. Weed control was less important due to the development of mulching method of ridge and ditch. Quality factors of raw ginseng in relation to red ginseng process were extensively studied. Traditional quality measures were elucidated in accordance with modern analytical chemistry resulting in the importance of peptides in the centrat part rather than ginsenosides For large root production growth promoting rootzone micrcorganisms (PGPRM) were isolated and active compounds were identified. Field test on PGPRM was on going. Varictus methods formality improvement through cultivation were developed. Management research of ginseng production was rare Extension was active throuch official and private organizations and through workshop for the extension specialists, and direct lectures to grower's. Extension services made the researcher to understand the existing problems at grower's fields. Research environment for ginseng production was in prime time only for three years when Korea Ginseng Research Institute was established then gradually aggravated.

• 아시안잔디학회지
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• 제24권1호
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• pp.9-15
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• 2010

2008~2009 겨울 동안 강원도와 전라북도 소재 골프장에서 분리한 황색마름병원균(Rhizoctonia cerealis Van der Hoeven)과 설부갈색소립균핵병원균(이하 설부병원균)(Typhlua incarnata Lasch ex Fr.)에 대한 화본과 식물과 잔디 종(품종)의 저항성이 실내에서 평가되었다. 분리균주의 병원성 검정결과 대부분의 잔디와 화본과 식물에 병을 일으켰지만 균주간의 병원력 차이도 발견되었다. 황색마름 병균은 잔디의 지제부위를 통해 감염하여 연한 갈색의 원형 반점 증상을 보이다가 진전되면 적색을 띄다가 결국 진한 갈색의 증상으로 나타났다. 설부병 증상은 수침형 반점으로 시작해서 전체 식물체를 갈색으로 고사시켰는데, 대부분 감염부위에서 흰색의 균사체가 식물체와 토양을 뒤덮었고 진전되면 다양한 크기의 갈색과 검은색의 독특한 균핵을 형성하였다. 병 발생은 습실기간이 길어질수록 증가하는 경향이었다. 화본과 작물과 잔디의 종(품종)간에는 병원균의 병원력에 차이도 나타났으며 두 병원균에 대해 양적인 차이를 보였다.