• Journal of Ginseng Research
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• 제23권3호
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• pp.135-147
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• 1999

Nine herbicide products (fluazifop-p-butyl, clethodim, MCPA-sodium, 2,4-0 amine, chlorthal dimethyl, diquat, glyphosate, ethalfluralin and oryzalin) were evaluated for use on ginseng (Panax quinquefolius). Products varied in their ability to suppress weeds and certain materials were phytotoxic to ginseng in some trials. Chlorthal dimethyl (broadleaf weeds), MCPA-sodium (broadleaf weeds), fluazifop-p-butyl (grass weeds), and clethodim (grass weeds) were found to be effective as weed control agents and did not adversely affect ginseng growth. Other products tested were either not efficacious or were phytotoxic to ginseng in some trials. Weed populations were mainly introduced into the planting sites via the straw mulches used in ginseng cultivation.

• The Plant Pathology Journal
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• 제24권4호
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• pp.461-468
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• 2008

An endophytic bacterial strain YC5480 producing antifungal and phytotoxic compounds simultaneously was isolated from the surface sterilized root of Artemisia sp. collected at Jinju area, Korea. The bacterial strain was identified as a species of Pseudomonas brassicacearum based on its 16S rRNA gene sequence analysis and physiological and biochemical characteristics. The seed germination and growth of monocot and dicot plants were inhibited by culture filtrate (1/10-strength Tryptic Soy Broth) of the strain. The germination rate of radish seeds in the culture filtrate differed in various culture media. Only 20% of radish seeds germinated in the culture media of 1/2 TSB for 5 days incubation. Mycelial growth of fungal pathogens, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora capsici was also inhibited by the culture filtrate of the strain YC5480. An antifungal compound, KS-1 with slight inhibitory activity of radish seed germination at 1,000 ppm and a seed germination inhibitory compound, KS-2 without suppression of fungal growth were produced simultaneously in TSB. The compounds KS-1 and KS-2 were identified to be 2,4-diacetylphloroglucinol (DAPG) and 2,4,6-trihydroxyacetophenone (THA), respectively.

• 아시안잔디학회지
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• 제12권3호
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• pp.183-194
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• 1998

21과 30종의 약용식물의 Rhizoctonia solani AG1-1(brown patch)와 R. solani AG2-2(large patch)에 대한 항균활성을 조사한 결과 계피, 목단피, 백선피가 강한 항균활성을 나타내었다. R. solani AG1-1에 있어 계피와 목단피는 100％ methanol로 추출한 것이 활성이 가장 높게 나왔으며 백선피는 80％ methanol로 추출한 것이 높게 나왔다. 반면에 R. solani AG2-2에 있어서는 모두 100％ methanol에서 활성이 가장 높게 나왔다. 농도별 활성은 이들 조추출물의 500배 희석액에서 60%이상 공시균주의 균사생장이 억제되었다. 항균specturum은 목단피가 가장 넓었다. 계피조추출물은 250배이상 희석액에서 목단피의 조추출물은 100배이상 희석액에서 약해를 나타내지 않았으며 백선피의 조추출물은 전혀 약해를 나타내지 않았다. 처리 30일후 방제가는 목단피 처리구 75.0％, 백선피 처리구 79.1%로였다.

• The Plant Pathology Journal
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• 제20권1호
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• pp.52-57
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• 2004

Sclerotinia sp. (isolate BWC98-105) causes stem blight and root rot in Leghum sp., and is presently being evaluated as a potential mycoherbicide for the control of Trifoliorium repens. Bioassays have shown that Sclerotinia sp. produces phytotoxic substance which is biologically active against T. repens. Two biologically active compounds, designated as compoundsI and II, were produced in vitro from the culture filtrate of BWC98-105 isolate Sclerotium sp. Compounds I and II were purified by means of liquid-liquid extraction and $C_{18}$ open column chromatography (300 ${\times}$ 30 mm, i.d). To determine the purity, the purified compounds were analyzed by RP-HPLC. The analytical RP-HPLC column was a TOSOH ODS-120T (150 ${\times}$ 4.6 mm i.d, Japan), of which the flow rate was set at 0.7 mL/min using the linear gradient solvent system initiated with 15 % methanol to 85 % methanol for 50 min with monitoring at 254 nm. Under these RP-HPLC conditions, compounds I and II eluted at 3.49 and 4.13 min, respectively. Compound II was found to be most potent and host specific. However, compound I had a unique antibiotic activity against phytopathogenic bacteria like bacterial leaf blight (Xanthomonas oryzae) on rice, where it played a less important role in producing toxicity on T. repens. No toxin activity was detected in the water fraction after partitioning with several organic solvents. However, toxin activity was detected in the ethyl acetate and butanol fractions. In the leaf bioassay using compound II, the disease first appeared within 4-5 h as water soaked rot, which subsequently developed into well-defined blight affecting the whole plant.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 추계학술발표회 요지
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• pp.210-211
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• 2005

• Toxicological Research
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• 제1권1호
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• pp.1-15
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• 1985

The trichothecenes are a chemically related sesquiterpenoid fungal metabolites of Fusarium, Trichoderma, Stachybotrys and others, and at moment more than 70 kinds of derivatives are identified. Historically, they are identified as antifungal and phytotoxic compounds, but after the finding of T-2 toxin from Fusarium tricinctum, several trichothecenes are now considered to be natural toxicants in foodstuffs and feeds.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.38-41
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• 2001

It has been reported that some plants have the potential to metabolize the 2,4,6-trintroluene (TNT) in contaminated soils, sediments and natural water. In this study, the effects of TNT on germination and early seedling development of Abutilion avicennae was characterized in a germination test. Concentration up to 80 mg/L TNT did not affect germination but root and shoot growth, and fresh biomass decreased as TNT concentration increased. A series of axenic hydroponical batch culture of Abutilion avicennae at various initial TNT concentration was used to determine its transformation kinetics, to identify products formed, and to evaluate phytotoxic effects on the TNT transformation process. At higher initial TNT concentrations, TNT removal rate constant decreased, however, total amount of TNT removed was increased in the culture media. Reductive transformation products of TNT were not detected in the plant culture media but higher concentrations of reduced metabolites were detected in the root and stem extracts of plant material at the 7 days of batch incubation. From these results we concluded that Abutilion avicennae has an intrinsic capacity for taking up and transforming TNT.

• The Plant Pathology Journal
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• 제26권3호
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• pp.245-252
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• 2010

An endophytic bacterial strain, Arthrobacter humicola YC6002, was isolated from a surface sterilized root of Korean turf grass (Zoysia japonica) collected from Jinju, Korea. This strain showed inhibitory effect on germination and shoot growth of radish. The inhibition of germination and shoot growth of radish seeds varied depending on the age of culture and the temperature at which it was incubated. The culture filtrate of 1/10-strength Tryptic Soy Broth medium, incubated for 48 hours at $30^{\circ}C$, showed the highest inhibitory effect on radish seed germination and shoot growth (92% inhibition as compared to control). The active compound with seed germination and shoot growth inhibition was purified and identified as 3-phenylpropionic acid. The purified compound had 53% and 93% inhibitory effect on seed germination and shoot growth of radish for 500 and 1000 ppm solutions, respectively.

• Journal of Microbiology and Biotechnology
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• 제18권1호
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• pp.138-144
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• 2008

The production of the entomopathogenic and phytotoxic cyclic depsipeptide beauvericin (BEA) was studied in submerged cultures of Fusarium oxysporum KFCC 11363P isolated in Korea. The influences of various factors on mycelia growth and BEA production were examined in both complete and chemically defined culture media. The mycelia growth and BEA production were highest in Fusarium defined medium. The optimal carbon and nitrogen sources for maximizing BEA production were glucose and $NaNO_3$, respectively. The carbon/nitrogen ratio for maximal production of BEA was investigated using response surface methodology (RSM). Equations derived by differentiation of the RSM model revealed that the production of BEA was maximal when using 108 mM glucose and 25 mM $NaNO_3$.

• The Plant Pathology Journal
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• 제16권3호
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• pp.137-141
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• 2000

A causal fungus of turfgrass blight was isolated from the infected leaves of zoysiagrass (Zoysia japonica Steud.) and identified as Nigrospora sphaerica (Sacc.) Mason by using a light misroscope. Its conidia are large (14-20 ${\mu}{\textrm}{m}$ diameter), shiny, black, aseptate, and smooth-walled spheres. The fungus caused typical blighting symptoms on the two turfgrass plants of bermudagrass (Cynodon dactylon (L.) Pers.) and bentgrass (Agrostis palustris Huds.). The fungus was found to produce a phytotoxic subtance to be associated with the pathogenic mechanism. A phytotoxin was isolated from the liquid cultures of N. sphaerica by repeated silica gel column chromatography and its structure was determined to be 5, 6-dihydro-5-hydroxy-6-propenyl-2H-pyr-2-one (T-3 compound). It was not a host-specific toxin showing phytotoxic effects to various plants inclusing turfgrasses in the leaf-wounding assay, the whole plant test, and the cellular leakage test. The compound caused leaf tip dieback symptoms in turfgrass plants similar to those caused by the pathogen. Thus, T-3 compound is thought to be involved in the development of Nigrospora blight.