• Journal of Life Science
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• v.11 no.6
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• pp.603-611
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• 2001

Phytolalexins are produced in plants affected by various environmental factors such as fungal infection treatment with many chemicals and irradiation by ultraviolet light. When pepper and tobacco bel suspension cultures were grown on a basal MS medium supplemented with 2,4-D(1mg/$\ell$, benzyl adenine(0.001 mg/$\ell$) and 100$\mu$ M jasmonic acid, the production of capsidiol was observed. The total of compound found in pepper plant were around seventy and thirty of them were located intissue-specific manner. 1-propanethiol, $\alpha$-D-xylofuranoside, phenol, hexadecanonic acid ethyl tridecanoate, phytol, linoleic acid and capsidiol are those which have change the production level by treatments, such as the inoculation of Phytophthora capsici Leonian, the metalaxyl treatment and the UV-B irradiation, respectively. The content of capsidiol on inoculation of P. capsici with metalxyl suspension in soil were higher than those of P.capsici without metalaxyl. When the soil dernch of metalaxyl treatment (1$\mu\textrm{g}$/${mu}ell$)was delayed after inoculation, the content of capsidiol were higher than that of before. Irrradiated UB-B the production on capsidiol was identified only at leaf, and contents were the highest for 24 hrs incubation after 20 minutes irradiation.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.1-11
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• 1987

This study was conducted to evaluate the effect of several fungicides and growth regulators on rice seedling growth and damping-off in seedling boxes for machine transplanting. Fungicide treated plots were better seedling growth, shoot regrowth, rooting ability, change of moisture content than those of nontreated plot. Metalaxyl application of Samgangbyeo and SF8002 application of Nagdongdyeo apparently increased plant height, length of the third leaf and fourth leaf. And metaiaxyl application highly increased dry weight. Fungicide treated plots were highly effective in reducing the incidence of damping-off. Benzyladenine application of Samgangbye and $GA_3$ application of Nagdongbyeo apprently increased plant height. But ABA application highly decreased plant height. ABA application and aCE application resulted in highly increased rooting ability. Fungicide and $GA_3$ treated plots, Metalaxyl and growth regulator treated plots resulted in highly increased plant height. I soprothiolane and growth regulator treated plots resulted in decreased plant height. Dachigaren and lAA treated plot apprently increased dry weight and shoot dry weight/plant height. Fungicide and growth regulator treated plots were highly effective in reducing the incidence of damping-off.

• 한국약용작물학회:학술대회논문집
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• 2007.05a
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• pp.127-128
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• 2007

• Korean journal of applied entomology
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• v.36 no.2
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• pp.179-184
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• 1997

This study was conducted to observe the effects of pesticides on the pathogenicity of entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae isolated from Korea. Spomlation of entomopathogenic fungi in SMAY medium that mixed different concentrations of pesticides was similar to control in metalaxyl and tolclofos- methyl treatment but in half recommanded treatment of fenitrothion and mepronil very poor spomlation was showed. Pathogenicity of entomopathogenic fungi dipped in all tested pesticide solution for 1 to 5hr was 100% pathogenicity of M. aniropliae in the pesticide treated chinese cabage fields were similar to control, Bt, teflubenzuron, metalaxyl, and carbofuran treatment but alachlol was below 80%. Pathogenicity and persistence of entomopathogenic fungi in turfgrass when pesticides were posttreatmented were continued to 4 months in iprodione+thiram and tolclofos-methyl treated plots but those of B. bassiana and M. anisopliae was losted in fenitrothion pathogenicity and persistence of in mepronil were nil M. anisopliae from 3 months after treatment.

• Korean Journal of Crystallography
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• v.13 no.3_4
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• pp.148-151
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• 2002

The molecular and crystal structure of metalaxyl C/sub15/H/sub21/NO₄, was determined by single crystal x-ray diffraction study. Crystallographic data for, title compound P2₁/c, a=7.849(4) Å, b=13.081(5) Å, c=15.100(3) Å, β=101.8(2)°, V= 1517.6(3) ų, Z=4. The molecular. Structure model was solved by direct method and refined by full-matrix least- squares. The final reliable factor, R, is 0.067 for 1694 independent reflections (F/sub o//sup 2/>4σ(F/sub o//sup 2/)). The molecular structure of title compound shows an intramolecular hydrogen bond: Cl2-Hl2A…O1.

• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.331-335
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• 1996

1993년 전북완주와 충남 서산 지역에서 생강 근경 부패병에 감염된 식물체로부터 Pythium sp.를 분리하였으며, 52균주를 형태적 특징과 병원성 검정을 통해 Pythium zingiberum으로 동정하였다. P. zingiberum으로 동정된 균주들이 재배지에서 사용되는 metalaxyl(MT), metalaxyl+copper oxychloride(MC), echlomezol(EM) 및 propamocarb hydrochloride(PC)등에 균사 생장, 난포자 형성에 미치는 영향 및 약제방제 효과 등을 검토하였다. MT, MC, EM 등이 혼합된 평판배지에서의 균사생육 정도는 50, 100 mg/L에서도 균사생장 억제를 나타냈으나 3균주는 EM 100mg/L에서도 균사생장이 저지되지 않았다. 100mg/L에서도 균사생육 억제효과가 적은 PC의 경우 저항성균주의 난포자 형성량은 약제 희석농도가 높아질수록 저하되었으나, 감수성을 나타낸 균주는 10, 50mg/L에서 오히려 증가하였다. 또한 폿트실험을 통한 약효검정 결과에서도 MT, MC, EM등은 대조구에 비해 생강 근경부패병을 억제하였다.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.04a
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• pp.40.3-41
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• 1999

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.49.3-49
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• 1999

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.360-365
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• 1993

The infant seedling of rice(8-to 10-day-old) has often suffered from submergence just after transplanting due to the too short seedling height, 5 to 8cm, This experiment was conducted to elucidate the effect of gibberellic acid($GA_3 : 25% soluble liquid) with the application methods of foliar spray and seed-soaking on the elongation of seedling height of infant rice seedling in machine transplanting, We used a japonica rice variety, Hwaseongbyeo, and the seeding rate was 200g per seed tray(30$\times60$\times3cm). Generally,$GA_3 and Metalaxyl increased the elongation of seedling height of infant seedling while Tetracycle decreased the seedling height, To increase the seedling height of infant seedling, the foliar spary application of $GA_3 was better than seed-soaking treatment. The optimum concentration of $GA_3 for the foliar spray was about l0ppm and the optimum application time of $GA_3 was 3 to 4 days after sowing.

• The Plant Pathology Journal
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• v.32 no.1
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• pp.16-24
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• 2016

In this study, antifungal activity of essential oils of Cymbopogon citratus and Ocimum basilicum and two fungicides Mancozeb and Metalaxyl-Mancozeb in six different concentrations were investigated for controlling three species of Phytophthora, including P. capsici, P. drechsleri and P. melonis on pepper, cucumber and melon under in vitro and greenhouse conditions, respectively. Under the in vitro condition, the median effective concen- tration ($EC_{50}$) values (ppm) of plant essential oils and fungicides were measured. In greenhouse, soil infested with Phytophthora species was treated by adding 50 ml of essential oils and fungicides (100 ppm). Disease severity was determined after 28 days. Among two tested plant essential oils, C. citratus had the lowest $EC_{50}$ values for inhibition of the mycelial growth of P. capsici (31.473), P. melonis (33.097) and P. drechsleri (69.112), respectively. The mean $EC_{50}$ values for Metalaxyl-Mancozeb on these pathogens were 20.87, 20.06 and 17.70, respectively. Chemical analysis of plant essential oils by GC-MS showed that, among 42 compounds identified from C. citratus, two compounds ${\beta}$-geranial (${\alpha}$-citral) (39.16%) and z-citral (30.95%) were the most abundant. Under the greenhouse condition, Metalaxyl-Mancozeb caused the greatest reduction in disease severity, 84.2%, 86.8% and 92.1% on melon, cucumber, and pepper, respectively. The C. citratus essential oil reduced disease severity from 47.4% to 60.5% compared to the untreated control ($p{\leq}0.05$). Essential oils of O. basilicum had the lowest effects on the pathogens under in vitro and greenhouse conditions. These results show that essential oils may contribute to the development of new antifungal agents to protect the crops from Phytophthora diseases.