• Research in Plant Disease
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• 제8권1호
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• pp.59-62
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• 2002

Anthracnose symptoms were observed on the community area in Sancheong-gun, Gyeongnam Province in Korea. The symptoms occurred on leaf and stem, and then plants eventually were died. Colony color was whitish gray to dark gray on potato dextrose agar. Conidia were single celled . colorless, cylindrical and was 10.2~20.4$\times$3.6$\times$6.0$\mu$m in size. Appressoria were dark brown, ovate to obovate and 6.2~10.5$\times$4.3$\times$8.6$\mu$m in size. Perithecia were brown to black in color and shaped as globose to obpyriform and 72.6~284.7$\mu$m in size. Asci were clavate to cylindrical in shape and 63.6~98.8$\times$8.3~12.5$\mu$m in size. Ascospores were cylindrical. fusiform, slightly curved at the center and 9.6~21.8$\times$4.0~6.0$\mu$m in size. Optimum temperature fur growth was 3$0^{\circ}C$. On the basis of mycological characteristics and pathogenecity test on host plants, the fungus was identified as Glomerella cingulata . This is the first report on the Anthracnose of achyranthes caused by Glomerella cingulata in Korea.

• Research in Plant Disease
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• 제13권1호
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• pp.15-19
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• 2007

A wilt disease on the greenhouse-grown chrysanthemum occurred at Kumi, Masan and Busan, Korea in $2003{\sim}2005$. Symptoms of wilting, yellowing, and marginal burning started from lower leaves and progressed upward. Early symptoms often appeared on one side, involving only one part of the plant or one side of individual leaves or stems without a vascular discoloration. Vascular tissues of the infected leaf-base's discolored to brown. Fungal isolates obtained from discolored tissues were identified as Verticillium dahliae based on its cultural and morphological characteristics. The fungus showed whitish to creamy colony pattern with abundant dark brown to black elongated microsclerotia on PDA. Conidiophores were verticillately branched and conidia were ellipsoidal to sub-cylindrical shape, and measured as $2.5{\sim}8.8{\times}2.0{\sim}3.8{\mu}m$. Pathogenicity tests by root dipping resulted in similar symptoms observed in the naturally infected chrysanthemum in fields.

• Korean Journal of Medicinal Crop Science
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• 제11권2호
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• pp.97-101
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• 2003

The purpose of this experiment is to improve the ratio of female flower in Schizandra chinensis Baillon. The experiment was carried out in two purposes. One was to understand the development stages on bud formation and determining sex after bud formation by stage. The other was to investigate characteristics of flowers forming on spring when summer pruning was taken place in different cutting part and timing in S. chinensis Baillon. The outcome was that on 7th of June the flower bud was found next to leaf primordium in branch of this year and no changes were found in shape for two weeks by 26th July. On 26th of June, an ovule that forms organ was observed and then, an ovule was found after sex was determined on 6th of July. Second experiment was carried out to find out when the sex was determined by adapting different pruning methods; cutting the branch at 6th node on June 1, June 15, and July 1; cutting the branch at 10th node on June 15, and July 1. The result was that the re-growth ratio on the branch 6th node was cut on June 1 and June 15. July 1 was 34-56% and, however, the number of setting flowers and mail flowers were fewer than the normal branches. More over, even though the re-growth ratio of branches were 34-25% when the cutting was taken place at 10th node on June 15 and July 1, the number of setting flowers and mail flowers were the same as the non treated branch. As a result, it is assumed that cutting controlling in this plant to increase the number of female flowers has no effect.

• Journal of Life Science
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• 제21권7호
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• pp.1004-1008
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• 2011

This study was conducted to investigate the effects of uniconazole (Sumiseven), an existing expensive growth retardant, and diniconazole (Binnari), used as a cheap germicide, on the growth and flowering of Vinca major and Salvia splendis for the possibility of substitution for expensive growth retardants. The growths of V. major and S. splendis were retarded by Binnari treatment. The effect of Binnari 100 mg/l treatment was higher than that of Sumiseven 5 mg/l treatment in both plants. The length of leaves was remarkably retarded by Binnari treatment, however, the width of leaves was only slightly retarded, giving the leaf a round shape. The number of days to flowering was increased by Binnari treatment in both in V. major and S. splendis. The number of days to flowering in V. major showed no significant difference compared to the control except by treatemtn with Binnari 400 mg/l. The number of florets of S. splendis increased with treatment with Binnari 100 and 200 mg/l.

• Korean journal of applied entomology
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• 제49권4호
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• pp.351-355
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• 2010

This study was conducted to determine the relationship of larval density of tobacco cutworm, Spodoptera litura (Fabricius) to damage in greenhouse sweet pepper. Laboratory experiments, cage experiments by artificial release and field investigation were carried out in 2008. The leaf consumption rate increased greatly with larval development. The damaged leaves had several round or oval shape holes on the surface or lost certain parts of them, and the fruit damaged had a conspicuous hole on the surface or scar marks around the calyx. In the field investigation, fruit damage was highly correlated with larval densities and reached 3.5% damage at maximum. Cage experiments showed that numbers of non-marketable fruit increased as increasing larval densities released. The larval density at two weeks before harvest had a high relationship with the percentage of damaged-fruit at harvest. Corresponding larval density caused 1, 3, 5% of damaged-fruit was 0.2, 0.5, 0.8 larvae per plant, respectively.

• Korean Journal of Plant Resources
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• 제24권4호
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• pp.370-378
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• 2011

To address infra-specific relationships of Sedum kamtschaticum Fisch., and to provide the fundamental information for developing new horticultural variations, we analyzed the morphology of individuals in four natural populations (Mt. Gwangdeok, Mt. Samyeong, Mt. Yonghwa, Tongyeong) and investigated the vegetations of these area. Based on 50 morphological characters the principle component analysis (PCA) has been performed. Principle component axis 1, 2, and 3 explain 22.9%, 14.2%, and 7.4% of total variations, respectively. Dot plot of OTUs in PC2 by PC1 area showed that the areas of four populations are completely overlapped. The result of PCA and the statistics of each character indicate that all of morphological characters are overlapped in these four populations. The maximum deviations are found in the characters related in the size and shape of the leaf. In the vegetation analyses, eighteen community plots that we investigated were grouped into 10 subcommunities: subcomm. Boehmeria spicata, subcomm. Artemisia stolonifera, subcomm. Artemisia keiskeana, subcomm. Impatiens nolitangere, subcomm. Crepidiastrum chelidoniifolium, subcomm. Urtica thunbergiana, subcomm. Artemisia gmelini, subcomm. Commelina communis, subcomm. Erigeron annuus-Artemisia princeps, and typical subcommunity.

• Research in Plant Disease
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• 제14권1호
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• pp.68-70
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• 2008

Brown leaf spots on leaves of kiwifruit(Actinidia deliciosa) were observed at farmers' orchards in Suncheon and Goheung, Jeonnam Province, Korea in June, 2006. They developed to form dark brown ring spots and severely infected leaves resulted in defoliation during the growing season of kiwifruit. Alternaria sp. was isolated from the diseased leaves repeatedly and was identified as Alternaria alternata on the basis of its mycological characteristics on potato dextrose agar and its pathogenicity was confirmed by wound inoculation on healthy leaves of kiwifruit. A. alternata formed gray to dark sooty gray colony and produced numerous conidia on potato dextrose agar. The conidia, commonly in long chains of 5 or more produced on conidiophores, have $3{\sim}5$ transverse and $1{\sim}2$ longitudinal septa and mostly ovoid or obclavate in shape and were pale brown golden brown in color. The condia were $16.5{\sim}42.1{\times}6.7{\sim}19.5\;{\mu}m$ in size and conidiophores were $8.6{\sim}112.7\;{\mu}m$ in length. This is the first report on the brown ring spot on leaves of kiwifruit caused by A. alternata in Korea.

• Journal of Sericultural and Entomological Science
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• 제35권1호
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• pp.60-68
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• 1993

It has been known that the silk degumming treated by hot alkali solution is easy to handle but is liable to yield poor-quality silk due to the degree of degumming loss, incomplete-degumming or over-degumming. Therefore, many studies have been carried out on the silk degumming by enzyme in order to improve the quality of silk. However, no attention has been paid to the physicochemical analysis of enzymatic degummed silk. In this paper, two different degumming methods, soap and enzymatic, are compared in aqueous solution state of silk fibroin. The results can be summarized as follows: There was no significant difference between two solutions on the bases of polarizing microscopy, TEM observation and SDS-PAGE. Spherulite of silk fibroin was not observed in polarizing microscopy, however the leaf-shape fibril structure was developed upon solidification. The size of spherulites of silk fibroin in TEM observation were 30~120nm with a wide range of size distribution. The intrinsic viscosity of enzymatic degummed fibroin solution was lower than that of soap degummed solution. This can be explained that the silk fibroin was more degraded by enzymatic degumming method compared with the soap degumming method. SDS-polyacrylamide gel electrophoresis showed that the fibroin molecule was composed of large component of molecule weight above 50 kd and small component of molecule weight about 20 kd. There was no difference in crystallinity between two degumming methods on the bases of results of DSC thermograms and IR spectra.

• The Korean Journal of Mycology
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• 제18권4호
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• pp.203-208
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• 1990

Sexual reproductive structure of Phytophthora capsici in vitro was round shape with thick wall and $24.4\;{\mu}m$ of diameter ranging $20-32.5\;{\mu}m$. Oogonium was $26.7\;{\mu}m$ $(21-37.5\;{\mu}m$) and $6.5-{\times}5.4m$ $(6-8{\times}5-6{\mu}m)$ for antheridium as doughnut shaped. Since mycelial contact of the paired cultures initiated right after inoculation, mycelial expansion phase was followed. Oospore morphogensis could be divided into the four phases for reproducing adult oospores. The optimum temperature for oospore reproduction was $20-24^{\circ}C$, whereas a retard trend for oospore formation was at the temperature above $25^{\circ}C$. Korean squash agar medium showed a higher oospore formation than the existing V-8 agar medium. Red pepper fruit agar medium was next. No oospore was reproduced on the red pepper leaf medium. Diurnal light with $1800{\pm}300$ and $800{\pm}300$ Lux showed rather retardation for oospore formation than dark conditions.

• Weed & Turfgrass Science
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• 제5권4호
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• pp.256-259
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• 2016

An obligate plant pathogenic fungus Puccinia zoysiae Dietel, the causal agent of rust disease, which is implicated in the damage of zoysiagrass (Zoysia spp.) in Korea. The fungus is one of the important pathogens, which attacks and colonizes susceptible zoysiagrass. Zoysia rust disease was observed in Jangseong, Hoengseong and Hapcheon in 2014 and 2015, Korea. The typical symptoms of the disease appeared first as small white spots on the leaf and stem of zoysiagrass plants, and turn brownish, dark brown spores revealed on the lesions. Uredospores were light brown in color, ellipsoid or spherical in shape and $22.0{\sim}25.0{\times}15.0{\sim}17.5{\mu}m$ in size. On the basis of the morphological characteristics, the fungus was identified as P. zoysiae. Pathogenicity of the fungus was proved by artificial inoculation on Z. japonica. The rust disease firstly appeared approx. early or middle June and then increased middle of October in Korea. In field, Z. matrella ecotypes were more resistant than Z. japonica ecotypes against the pathogen. Disease response against the pathogen was different among ecotypes of each species, respectively.