• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.725-728
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• 1998

Phytophthora crown rot of cymbidium was observed in Cheju island since June of 1996. The disease initiated at the basal portion of infected plant progressed upward to lower leaves. Soon after distinct water-soaking lesions appeared on lower leaves, the plant was wilted, blighted and died. Four orchid farms at Sogwipo out of 16 surveyed in the island were infected by the disease estimating 5~20% infection rates. The causal fungus was identified as P. palmivora based on following distinguishing characteristics. All isolates were heterothallic as A1 types and readily produced chlamydospores with cultural age. Sporangia were conspicuous papillate, ellipsoidal to ovoid, highly deciduous with short pedicels ca. 3~4 ${\mu}{\textrm}{m}$. Koch's rules were satisfied by a pathogenicity test and re-isolation of the fungus from inoculated plants. The pathogen has never been reported in Cheju island previously and its firstly recorded as the cause of Phytophthora crown rot of cymbidium in Korea.

• Research in Plant Disease
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• v.22 no.3
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• pp.190-193
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• 2016

In 2010 and 2012, damping-off symptoms were found on melon seedlings grown in Yeongam and Suncheon, Korea. Water-soaked and discolored lesions appeared on the lower stems of the infected plants. The diseased plants became wilted and stunted, and eventually collapsed. On the basis of morphological characteristics and molecular analyses of internal transcribed spacer (ITS) rDNA and cytochrome oxidase II (cox2) sequences, the causal organism was identified as Pythium spinosum. The isolates were pathogenic to melon under pot conditions. To our knowledge, this is the first report of P. spinosum causing damping-off on melon in Korea.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.387-390
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• 2005

A survey was conducted during February-March 2003 to determine the occurrence and population density of plant-parasitic nematodes in strawberry (Fragaria ananassa) fields, cultivated under plastic houses in major strawberry growing regions of Gyeongbuk and Chonbuk provinces, Korea. The survey revealed presence of eleven species of plant-parasitic nematodes viz., Aphelenchoides fragariae, Criconemoides morgensis, Ditylenchus dipsaci, Helicotylenchus dihystera, Hirschmanniella imamuri, Meloidogyne arenaria, M. incognita, Pratylenchus penetrans, Psilenchus hilarulus, Tylenchorhynchus claytoni and Xiphinema sp. Frequency and density of each species were highly variable from field to field and within the field. Plant growth was not uniform in the surveyed fields under plastic houses; stunted growth, chlorotic leaves, small curled or crinkled leaves, deformed buds and flowers and wilted plants with fewer fruits were observed in patches.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.978-980
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• 2010

This study was conducted to observe the cause of injury of fig plant. Nitrogen dioxide gas can be evolved at low pH or reduced in soil. Fig plant cultivated with nutrient solution was wilted or withered. Injury symptom for nutrient solution containing nitrous acid was worse as pH of soil decreased. However, increase in pH of nutrient solution treated with increasing $Ca(OH)_2$ solution prevented nutrient solution from producing nitrogen dioxide gas. Recovery of the fig plant by pH increase indicated that the cause of injury was nitrogen dioxide gas.

• The Korean Journal of Mycology
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• v.50 no.3
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• pp.249-254
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• 2022

In June 2021, foot rot symptoms were observed in wasabi (Eutrema japonicum) plants growing in vinyl greenhouses of the Alpine Agricultural Experiment Station, Wild Vegetable Research Institute, in Taebaek, Gangwon Province, Korea. Diseased plants displayed black soft rot of crowns and petioles at the soil line and wilted. The incidence of diseased plants was 2-10% in four out of five vinyl greenhouses investigated. Eight fungal isolates were obtained from diseased plants. All the isolates were identified as Phytophthora pseudocrytogea based on their morphological characteristics and phylogenetic analysis. Three isolates of P. pseudocrytogea were used for pathogenicity test on wasabi plants via artificial inoculation. The pathogenicity of the isolates was confirmed in the inoculated wasabi plants. The symptoms shown by the inoculated plants were similar to those observed in plants from the investigated vinyl greenhouses. This is the first report of P. pseudocryptogea causing Phytophthora foot rot in wasabi.

• Korean Journal of Environmental Agriculture
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• v.24 no.1
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• pp.56-60
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• 2005

In order to increase the storage stability of watermelon stalk, storage environments such as temperature and other treatments such as vaseline, mixture of soybean oil and wheat flour, and coated paper label were tested separately after harvesting. At different storage temperatures (7, 18 and $30^{\circ}C$) shelf-life of stalk was inversely proportional to temperature. The results showed that during storage at $30^{\circ}C$ they were completely wilted in 7 days, at $18^{\circ}C$ in 15 days and at $7^{\circ}C$ in 19 days. Our data also showed that stability of watermelon stalk depending on temperature was very closely correlated with water content of watermelon stalk; during storage at $30^{\circ}C$ the water content of watermelon stalk was decreased to 21.1 % in 7 days, whereas at $7^{\circ}C$ the water content was decreased gradually to 71.2 % for 19 days of storage. In order to reduce the physiological changes in watermelon stalk at $30^{\circ}C$, following treatments such as vaseline, mixture of soybean oil and wheat flour, and coated paper label were tested. As a result, watermelon stalk without any treatment was completely wilted in 9 days, while stalks treated with vaseline and mixture of soybean oil with wheat flour were wilted in 15 and 12 days, respectively. The wilt delay was noted in the watermelon stalk for $3{\sim}6$ days during both treatments but the outward quality was found detracted, whereas when treated with coated paper label, the wilt of stalk was delayed for 3 days along with the improvement in the outward quality. Therefore this data indicate that the treatment of coated paper label during storage at $30^{\circ}C$ can be considered as a potent method for maintaining the physiology of watermelon stalk.

• Korean Journal of Organic Agriculture
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• v.17 no.4
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• pp.519-527
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• 2009

The main nutritional problem of sorghum$\times$sudangrass hybrid silage is low quality and dry matter (DM) contents. This experiment was conducted to evaluate whether field pre-wilting treatment of sorghum$\times$sudangrass hybrid silage increases DM content and forage quality of the silage. The experiment was a randomized complete block design with three replications. The treatments were consisted of five different wilting days: 0 day (direct cut silage), 0.5 day, 1 day, 2 days and 3 days. Sorghum$\times$sudangrass hybrid silage with pre-wilting showed low 4.00 pH values, however direct cut silage (control) showed a 4.30 value because of its high moisture content. The DM content of sorghum$\times$sudangrass hybrid silage with pre-wilting was high above 25.1% after 1 days, however that of direct cut silage had 17.6%. And the effluent of wilted silage was decreased with prolonged wilting period, but that of direct cut silage produced effluent of 183 mL/kg. Crude protein and ether extract with wilted silage were decreased, however crude ash was increased with prolonged wilting period. Silage with pre-wilting had higher acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents than control silages, while its non-fiber carbohydrate (NFC) showed the opposite results. Lactic acid and total organic acid were increased with prolonged wilting period. For the palatability of dairy goat, silage with 2 days wilting was highest among silages. The experiment results indicate that wilted sorghum$\times$sudangrass hybrid silage could be recommended as effective method for reducing effluent, increasing pH and forage quality more than direct cut silage. Optimum pre-wilting day of sorghum$\times$sudangrass hybrid silage may be 1 days.

• Journal of The Korean Society of Grassland and Forage Science
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• v.1 no.1
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• pp.18-28
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• 1978

To study about the effect of harvested stage and physical treatment such as wilting or chopping of plant material on the quality of silage, Italian ryegrass(Lolium multiflorum) harvested at pre-headed or heading stage and Seombadi(Dystaenia takesimana Nakai) harvested at pre-flowering stage, were used for the purpose. The materials were treated in four different ways which were a) non-treated, b) one day-wilted, c) chopped with 1 to 2cm length and d) wilted and chopped, and those were ensiled in plastic containers and stored at room temperature for three months. After three months of storage, it was investigated and obtained the following results. 1) Having 6.31 of NFE/CP ratio and low content of crude fiber, Seombadi contained more suitable constituents for silage than Italian ryegrass. 2) Under the non-treated or chopped condition, the loss of NFE was higher, and lower with wilted material. 3) Wilting or chopping improved DM digestibility. 4) Compared with Italian ryegrass harvested at pre-headed stage, the storage amount per unit volume of heading stage-Italian ryegrass and Seombadi were higher 8% and 69% respectively, and wilting and/or chopping increased the storage amount 41 to 134%. 5) The majority of weight loss during storage was observed at 1st week after ensiling, it continued slightly until 4th week. The highest loss in 8th week were 3.76% of nontreated material. 6) One day wilting increased DM content of silage 23 to 131%. Wilting and chopping increased pH and lactic acid improved the quality considerably. 7) The correlation between $NH_3$ and butyric acid, and between lactic acid and DM were r=0.782**, r=0.634** respectively. The regression equation were y=12.853X+4.908 (X=butyric acid), y=0.016X+1.309(X=DM content), respectively. 8. The above results indicate that it is necessary to wilt or chop material to make good quality silage from Italian ryegrass, and such treatment can improve the quality of silage with Seombadi also.

• Korean Journal of Agricultural Science
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• v.2 no.1
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• pp.179-185
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• 1975

This trial was conducted for the selection of drought registance strains and other main characters of orchard grass. Some preliminary results obtained are as follows : 1. The initial growth of orchard grass in sufficient soil moisture condition showed highly significant differences among the varieties. Turkey's D=0.84. However, in proceeding the growth, the grass height among the varieties showed non-significant. 2. Addition of nitrogen fertilizer before first flowering tended to increase the grass height occationally significantly, compared to the control. 3. The survived varieties on the drought soil moisture condition had more numbers of tillering than the wilted significantly except some varieties. However, in grass height between the survival and the wilted, almost varieties showed non-significant differences. 4. In the varierties of Metia, Phyllox and Dorise, all individuals were survived in drought soil moisture condition and showed almost the same growth responces with willted ones comparatively. The plant height and the numbers of tillering of these 3 varieties were as follows: Merita; 26.4 cm 24.2 ea, Phyllox; 31.4 cm 24.6 ea. Dorise; 26.8 cm 35.6 ea.

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.297-312
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• 2020

Wilted soybean plants were collected from soybeans cultivation fields in Korea from 2014 to 2016. Fusarium spp., Colletotrichum spp., Rhizoctonia spp., Macrophomina sp., Phytophthora spp., and Calonectria ilicicola were obtained from the infected samples. Out of these, Fusarium spp. were the dominant species (79.1%). In total, 53 isolates were identified as F. solani species complex, F. oxysporum species complex, F. graminearum species complex, and F. fujikuroi species complex based on mycological characteristics. Sequence typing analysis was conducted using translation elongation factor 1 alpha (TEF) to confirm the identification of isolates. All isolates were identified as F. solani, F. oxysporum, F. commune, F. asiaticum, and F. fujikuroi based on phylogenetic analysis of TEF sequences. Pathogenicity of 44 isolates was tested on three cultivars of soybean using the root dip inoculation method. Out of 5 Fusarium species, only F. asiaticum could not cause the symptoms or be weak. Ten isolates were selected based on pathogenic characters and species identification to investigate the host range and screen soybean cultivars for resistance. Fusarium solani, F. oxysporum, and F. commune were aggressive only to soybean, and F. fujikuroi was aggressive to kidney bean, yellow cowpea, black cowpea, adzuki bean as well as soybean. All 13 Korean soybean cultivars were susceptible to F. commune and F. fujikuroi. Out of 13 cultivars, cv. Janggi, cv. Poongsannamul, and cv. Socheongja were resistant to Fusarium wilt, while cv. Hwanggeumol and Chamol were susceptible to Fusarium wilt.