• Journal of Ginseng Research
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• v.27 no.4
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• pp.202-206
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• 2003

This study was conducted to compare the growth status of aerial parts, photosynthesis and microclimate between fixing light transmittance (Control) and changing light transmittance (C.L.T.) during ginseng growing seasons. Control showed 8％ light transmittance rate during growing seasons. But C.L.T. showed 18％ light transmittance rate during early (April-June) and late growth stage (September-October) and 6％ light transmittance rate middle growth stage(July-August). Air temperature, leaking water rate and soil water content of C.L.T. was higher than those of control during early and late growth stage. But Air temperature, leaking water rate and soil water content of C.L.T was lower than those of control during middle growth stage C.L.T. exhibited superiority in survival ratio, stem diameter, stem length, L.A.I. and stem angle compared to control. Chlorophyll content of C.L.T. was lower than that of control but S.L.W., stomatal opening and photosynthetic rates of C.L.T. was higher than those of control. Also Alternaria blight disease and defoliation of C.L.T. was lower than those of control.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.162-166
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• 1997

Variations in growth and yield of adlay(Coix lachyma-jobi var. ma-yuen Stapf) was monitored in farmer's fields in Yunchon, the main producing area in Korea, where the field condition showed difference in topograyphy, crop rotation, and ridge shape. Rotation cropping increased remankably stem length, and number of effective tillers, reduced the occurrence of leaf blight and crop damage by the disease, and in addition showed positive effect to repress the occurrence of stem-borerin upland field. Stem length was greater in upland field than in paddy field and this result seemed to be related to lodging degree. The even field with crop rotation system showed the highest seed yield and followed by hillside field and paddy field resulted the lowest yield.

• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.56-61
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• 1997

This research was conducted to investigate morpological and growth characteristics of 358 Coix lacryma-jopbi mayuen STAF collected in Korea. The test collections contained 76% medium wide-type leaf, 59% medium size-type seed, 34% large size-type seed, 70% elliptical-type shell, 50% brown shell color, 92% low stem color and hardness of seed coat averaged $3.4kg/cm^2$ with the range of $1.1{\sim}18.7kg/cm^2$. 24% adaptable plant height ranged from 156cm to 170cm, days to heading after seeding averaged 83.2% with the range of $74{\sim}94$ days, early maturating varietes was 24.9% below 80 days. Rate to leaf blight 48.5% with the range of $9{\sim}92%$ and rate to stem borer averaged 8% with the range of $0{\sim}17%$. The weight of 1000 seeds showed positive correlation with days to flowering and plant height and number of seeds per plant showed positive corrleation with percentage of ripness, but weight of 1000 seeds showed negative correlation with occurrence of leaf blight and stem borer plant. Therefore we are expecting useful germplasm and selectable index for effective breeding.

• Asian Journal of Turfgrass Science
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• v.6 no.2
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• pp.99-111
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• 1992

Yellow patch as leaf blight caused by binucleate Rhizoctonia occured in bentgrass (Agrostis Palustris Huds), zoysiagrass (Zoysia japonica Steud) and Kentucky bluegrass (Poa pratensis L.) from several golf couses in Korea. Binucleate Rhizoctonia was isolated from the infected lesions and was identified Rhizoctonia cerealis. Rhizoctonia cerealis infected crown, stem and leaf tissue, and the symptom was light yellow circular patch upto 1 m in diameter on bentgrass golf green. Individual infected leaf near the margin of patch developed first red and finally turn brown. As zoysiagrass lawn, the symptom was 30~40cm circular patch that occured zoysiagrass shooting time as spring, and there could not sheeted in severe lesion. In case of sheeted, zoysiagrass was first irregular leaf sopt and finally dead. Hypha diameter of Rhizoctonia cerealis was $2.5~6.3\mu\textrm{m}$(average $3.8\mu\textrm{m}$) and colar was white to buff. Monilioid cell size was $5.8~12.5$\times$13.8~37.5\mu\textrm{m}$. Sclerotia size was 0.2~2.0mm and color was white to brown. Optium temperature for the hypha growth was $23^{\circ}C$. There was a little difference in pathogenicity among the isolates.

• Research in Plant Disease
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• v.17 no.2
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• pp.121-128
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• 2011

Bacteriolytic myxobacteria have been known to secrete various antifungal metabolites against several soilborne phytopathogens including Phytophthora. Among the three isolates of Myxococcus spp., KYC 1126 and KYC 1136 perfectly inhibited the mycelial growth of Phytophtora capsici in vitro. In order to show the biocontrol activity on Phytophthora blight of hot pepper, we tried to find the best way of application of a myxobacterial isolate. Although KYC 1126 fruiting body was easily grown on the colony of Escherichia coli as a nutrient source, it did not control the disease when it was pre-applied in soil. Before the bioassay of a liquid culture filtrate of KYC 1126 was conducted, its antifungal activity was confirmed on the seedlings applying with the mixture of the pathogen's zoospore suspension and KYC 1126 filtrate. On greenhouse experiments with five and four replications, the control value of KYC 1126 on phyllosphere and rhizosphere was 88% and 36%, respectively. Whereas, the control value of dimetnomorph+propineb on phyllosphere was 100% and that of propamorcarb on rhizosphere was 44%. There was a phytotoxicity of the myxobacterial filtrate when seedlings were washed and soaked for 24 hours. Gummy materials were covered with roots. And stem and petiole were constricted, then a whole seedling was eventually blighted.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.855-868
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• 2014

Synthetic agro-chemicals have been widely used to control diseases on paprika but these days negative attention has been increasing to use of them because of several adverse effects. This research was conducted to isolate and to characterize the antagonistic microorganism to control major paprika diseases, gray mold rot, fruit and stem rot, phytophthora blight, sclerotium rot, and wilt disease. Analysis of the fatty acid and analysis of the 16S rDNA gene sequence revealed that YKJ1 isolated in this research belongs to a group of Serratia marcescens. Specially, 16S rDNA gene sequence of YKJ1 showed 99% of sequence similarity with S. marcescens. Observation through the optical microscope revealed that YKJ1 suppressed the spore germination and the hyphal growth of pathogens. YKJ1 treatment on pathogens induced marked morphological changes like hyphal swelling and degradation of cell wall. In the case of phytophthora blight, the zoosporangium formation was restrained. S. marcescens found in this study call as S. marcescens-YKJ1 and it may be valuable as one of biological control agents against major diseases of paprika in the future even though it is require to be tested with more study on field test.

• The Korean Journal of Mycology
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• v.9 no.4
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• pp.169-176
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• 1981

Survey of sesame crop in the cultivators' field in the district of Daejeon, Yuseong, Sintanjin, Nonsan and Keumsan revealed that Alternaria and Corynespora blights of sesame were wide spread and caused severe damage to sesame plants. Symptoms of a new disease of sesame in Korea caused by Alternaria sesami were spreading, dark-brown to black, water-soaked lesions which often could be traced the entire length of the stem. In severe infections, several lesions coalesced together involving a major portion of the blade and the infected leaves dried and usually dropped off. Symptoms of Corynespora blight, caused by Corynespora cassiicola, were irregular shaped, concentrically-zoned, light brown to reddish brown lesions which later coalesced and caused defoliation. Stem lesions were long, reddish brown streaks that often coalesced, blighting the plants. The optimum temperatures for mycelial growth of A. sesami and C. cassiicola were about $27^{\circ}C$ and sporulations of these 2 fungi were stimulated under alternating light and darkness. Mycelial growth and sporulation of A. sesami and C. cassiicola were the greatest on sesame oatmeal agar (SOA) and potato dextrose agar (PDA), respectively.

• Research in Plant Disease
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• v.15 no.3
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• pp.259-261
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• 2009

Sclerotinia shoot rot of Grapevine(Vitis labruscana) occurred at Gapyeong and Yeongwol area from 2003 to 2005. Infected plants showed shoot blight at the one-year-old fruit bearing branches. The first visible symptom noticed was wilting and blighting of the branches. The obvious and typical initial symptom is the presence of a cottony, white, dense mat of mycelial growth on the surface of the diseased lesions. The base or stem of the infected young shoots develop a pale brown rotted area, which girdled and killed shoots. In advanced stages of the disease, stems and branches became bleached and eventually died. The isolates collected from diseased grapevine stem were identified as Sclerotinia sclerotiorum based on the morphological and cultural characteristics. The pathogenicity test revealed that Vitis vinifera(cultivar: Kyoho) was stronger than V. labruscana(cultivar: Campbell early) to the pathogen. This is the first report on sclerotinia shoot rot of grapevine in Korea.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.45-45
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• 2019

This experiment was carried out using artificial clay and LED in the plastic film house (irradiation time: 08:00~18:00/day). Seedlings (n = 63 per $3.3m^2$) of ginseng was planted on May 17, 2018. LED was combined with red and blue light in a 3:1 ratio and irradiated with different light intensity. The average air temperature from April to September was $12.3^{\circ}C$ $-26.0^{\circ}C$ and it was the the highest at $26.0^{\circ}C$ in August. The test area where fluorescent lamp was irradiated tended to be somewhat higher than the LED irradiation area. The chemical properties of the test soil are as follows. pH levels was 5.3~5.5, EC levels 0.45~0.52 dS/m and OM levels 33~37%. The total nitrogen content was 0.35~0.47% and the available $P_2O_5$ contents was 13.7~16.0 mg/kg, which was lower than the suitable level of 70~200 mg/kg. Exchangeable cations K and Mg contents were within acceptable ranges, but the Ca contents was $28{\sim}38cmol^+/kg$ levels higher than the permissible level ($2{\sim}6cmol^+/kg$). Germination of ginseng leaves took 8~9 days and the overall germination rate was 70~75%. The photometric characteristics of LED light intensity are as follows. The greater the light intensity, the higher the PAR (Photosynthetic Action Radiation) value, illuminance and solar irradiation. Photosynthetic rate was also increased with higher light intensity was investigated at $1.7{\sim}3.2{\mu}mol\;CO_2/m^2/s$. Leaf temperature ($23.7{\sim}24.8^{\circ}C$) by light intensity was the same trend. The growth of aerial parts (plant height etc.) were generally excellent when irradiated with 3 times the light intensity, the growth of the ginseng aerial parts were excellent as follows. The plant height was 42.6 cm, stem length was 25.2 cm, leaf length was 9.6 cm and stem diameter was 5.0 mm. The growth of underground part (root length etc.) was the same, and the root length was 24.4 cm, the tap root length was 6.0 cm, diameter of taproot was 18.2 mm and the fresh root weight was 17.2 g. There were no disease incidence such as Alternaria blight, Gray mold and Anthracnose. Disease of Damping off occurred 2.2~3.6% and incidence ratio of rusty root ginseng was 14.6~20.7%. Leaf discoloration rate was 13.7~48.9% and increased with increasing light intensity. Ginsenoside content of ginseng by light intensity is under analysis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.342-351
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• 1990

Experiments were conducted to find out the possibilities of producing good quality seed of summer type soybean at Chuncheon, 74m above sea level and Jinboo, 600m above sea level in 1987. Local variety, Cheonan Jaelae was used. Seeds were sown June 25 harvested five times from 35 days after flowering with five days interval to 55 days. Vegetative period was longer in the early planting and high cool area, Jinboo, which resulted longer stem length than the late planting and in the plain area, Chuncheon. Pod number and 100 grain weight were shown more and heavier in Jinboo. Earlier planting and later harvesting resulted more pod number and heaveier 100grain weight. Grain yield was heigher in Jinboo, and earlier plainting shown more grain yield and its difference was greater in Jinboo. Long grain filling duration resulted more grain yield. Unripened seeds were produced more by earlier planting with earlier harvesting and earlier planting with late harvesting showed the high rates of pod and stem blight (Diaporthe Phaseolorum). Seed With high moisture content by early harvesting showed more rotten seeds in all planting dates production was more advantageous in the high cool area, Jinboo. Optimum planting date was between May 15 and June 5. Harvesting was desirable about 45-50 days after flowering with heigher germination rate seed yield.