• Research in Plant Disease
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• v.8 no.1
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• pp.34-40
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• 2002

Different types of smut fungi have been reported from different geographical places, depending on the distribution of host plant. Therefore, a survey was conducted to investigate the host plant of smut fungi and occurrence situations in three Asian countries. As a result 12 genera of 4 families and 19 species,24 families 87 genus and 191 species, and 12 families 140 species were occurred in Korea, Japan and China, respectively. Six genera(Enty-loma, Yilletia, Sorosporium, Sphacelotheca, Urocysitis, Ustilago) of korean smut fungi species were reported until 1998. In Japan, Ito reported for first time 14 genera and 140 species of smut fungi in 19361 and then were more described into 17 genera 114 species by Kaki hits a in 1984. Two genera (Schizonella and Namnfldtiomyces) and 8 species were newly listed, later by other researchers. In China, Ling reported that smut fungi classified into 14 genera, 109 species in 1953. In addition, Liroa, Glomosporium, Gahmphopora and Microbotryum genus including 49 species were recently reported, thus 18 genera and 158 families of smut fungi in China. These results suggest that the number of plant related with smut fungi is seemed to be more increase in future. Smut disease, occurred on the whole or part of plant and flower.

• Korean journal of applied entomology
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• v.22 no.1 s.54
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• pp.1-6
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• 1983

The survey on the occurrence and distribution of barley stripe disease was conducted in the farmer's field of 19 gun (county) throughout Yeongmm area in May of 1982, in order to obtain a basic information on the breeding of resistant varieties, and for control of the disease. The percent of infected culms of barley stripe disease in Gyeongnam province (Southern Yeongnam) was higher $(13.7\%)$ them in Gyeong-bug $(6.9\%)$, northern Yeongnam, and especially, Ham-an, Milyang, Eui-chang and Weol-seong were severly occurred. The cultivar of Millyang 6 was slightly infected while the cultivars Olbori and Oweolbori were severely infected by the disease. Among soil conditions, the barley plant grown in the loam, clay and clay loam texture which have more availble moisture, and that of the plant cultivated in the poorly drained soils were shown to have severe infection. The barley plant grown in the soils in local valley $(18.8\%)$ where is frequently over saturated with water showed the more infection the barley plant grown in plains $(9.5\%)$. Generally, the poorer the soil drainage the more severeinfection occurred. Among cultivation conditions, the earlier the sowing dates of the barley, the less the percent of infected culms was observed. The heavier or lighter application of N fertilizer than the optimum to barley plant seemed to cause more infection.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.223-227
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• 2003

Survey on plant diseases occurring on cucumber cultivated in plastic film house of experimental farm in Suwon was conducted. Through the survey, occurrence of damping-off, downey mildew, powdery mildew and Fusarium wilt was observed. Especially downey mildew caused by Pseudoperonospora cubensis was the most severe foliar disease of cucumber. To control the disease effectively, effects of installation of ventilation fan and optimal spray timing of a chemical, dimethomorph+copper oxychloride WP, were investigated. Two ventilation fans installed at the front and at the back of plastic film house reduced air relative humidity by about 6.4% and downey mildew incidence by 55.7%. Downey mildew incidence on cucumber from untreated chemicals plot in plastic film house installed with ventilation fan was on a equal level with that from treated chemicals plot with three times application of dimethomorph+copper oxychloride WP in plastic film house without ventilation fan. Meanwhile in order to select optimal chemical application time, dimethomorth+copper oxychloride WP was treated three times at 7 days-interval from three days before the disease occurred, right after the disease occurred, and two days after the disease occurred, respectively. The result showed that dimethomorth+copper oxychloride WP applied to cucumber leaves and stems from three days prior to, right after, two days after occurrence of downey mildew reduced downey mildew incidence by 72.9, 61.8, and 23.7%, respectively. The above results showed that regulation of environmental factors like air relative humidity and preventive application of chemicals should be considered to establish control strategy to downey mildew.

• The Plant Pathology Journal
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• v.22 no.4
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• pp.309-313
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• 2006

Phytophthora blight(PB), caused by Phytophthora drechsleri f. sp. cajani is the third potentially important disease of pigeonpea in the Deccan Plateau(DP) of India after wilt and sterility mosaic. In the rainy-season of 2005, an outbreak of PB was seen throughout DP. To quantify the incidence and spread of the disease, a systematic survey was conducted in the major pigeonpea growing regions of DP during the crop season 2005. Attempts were made to determine the effect of cropping systems on the PB development and identify resistant cultivars, if any, grown by farmers and on research farms. Widespread incidence of PB was recorded on improved, and or local cultivars grown in different intercropping systems. Majority of improved cultivars grown at research farms were found susceptible to PB(>10% disease incidence). Pigeonpea intercropped with groundnut, black gram and coriander had less disease incidence(${\leq}10%$). Three wilt and SM resistant pigeonpea cultivars KPL 96053, ICPL 99044, and ICPL 93179 were found resistant(<10%) to PB as well. However, their resistance to PB needs confirmation under optimum disease development environments.

• Research in Plant Disease
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• v.7 no.1
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• pp.11-15
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• 2001

Root rot of Cucurbitaceae plants, caused by Monosporascus cannonballus, is one of the recently described diseases in Korea. The distribution and pathogenicity of M. cannonballus were examined by field and in vitro experiments. Root rot caused by M. cannonballus occurred on melon, oriental melon, watermelon and cucumber plants. In two years of disease survey, the disease occurred at 10 and 32 fields in 1997 and 1998, respectively, which were located at Kimhae, Chinju, and Namhae in Kyeongnam province, at Kwangyang in Chonnam province, at Kwangju city, and at Yeoju and Inchon in Kyeonggi province. The disease progress in a melon field at Namhae was not observed until the middle stage of plant growth, but rapidly increased at the fruit maturing stage, resulting in more than 50% yield loss. Isolation rate of M. cannonballus was 36.7% from wilted hosts. Fusarium oxysporum and Rhizoctonia solani were also frequently isolated. In vitro test, seedlings wilted after 7∼14 days of inoculation, and perithecia were formed in infected roots 21 days later. Two cucumber cultivars, Baekbong and Eunhwa, were resistant to the disease.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.308-313
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• 2007

A survey of the occurrence of abiotic diseases on kiwifruit (Actinidia deliciosa) trees was conducted at sixty-two kiwifruit orchards in twenty-one locations of Jeonnam and Jeju Provinces in Korea during the 2007 growing season. Various kinds of abiotic diseases were detected on the kiwifruit trees. Malformed fruits caused by incomplete pollination were commonly observed among the normally growing fruits on almost all of the kiwifruit trees examined. Fruits imbued with wire rust, fruits scratched or girdled by the wire and fruits injured by sunscald occurred in all of the examined orchards. Abnormal growth of girdled branches by the fence wire, dead trees killed by excessive soil moisture due to poor draining and leaf chlorosis by nutrient deficiencies were found in some orchards. Leaf spotting by herbicide and leaf scorch or blight by excessively high temperature were observed. Leaf blight on young shoots by late frost and bark split on trunks by freeze occurred in several open-field orchards. Flooding and strong wind damages by attack of typhoon 'Nari' were also found during the survey period. Cup-shaped leaves frequently occurred on young shoots in early spring and the incidence of the syndrome tends to increase annually in recent years, which are not etiologically defined until now.

• Research in Plant Disease
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• v.7 no.2
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• pp.102-106
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• 2001

Currently the rice false smut caused by Ustilaginoidea virens (Cooke) Takah. has occurred widely in Korea. A survey on the disease incidence at rice fields in 8 inland provinces was carried out in 2000, showing that the disease occurred at 104 (7.5%) out of 1,152 rice fields examined, ranging from 1.5% to 13.7% in provincial average. It was found that the disease incidence was greatly affected by local weather conditions and rice cultivars. In case of the most susceptible cultivar Namchunbyeo, the disease incidence was only about 1.3% in Icheon, while it was over 20% in Namwon which had weather conditions of the shorter sunshine period (about 64%) and the higher amount of precipitation (about 130%) during the rice cultivation than Icheon. In Icheon, artificial inoculation of the pathogen failed to induce the disease, probably because of the weather conditions unfavorable to the disease development, which also suggests that its incidence may be dependent on the weather conditions. Susceptibility of rice cultivars to the disease varied greatly; eight resistant cultivars including Heukjinjubyeo were not damaged by the disease, but 2 cultivars including Geumnambyeo and Namchunbyeo were severely damaged, having more than 20% of the disease incidence. Among chemicals tested fur the control of the rice false smut tebuconazole WP showed the highest control efficacy of 83∼88% on cvs. Geumnambyeo and Namchunbyeo. Other chemicals such as azoxystrobin WP and ferimzone WP also effectively suppressed the disease development in the field trials.

• Research in Plant Disease
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• v.17 no.2
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• pp.232-234
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• 2011

During survey of postharvest diseases of vegetables in the middle region of Korea in 2003, 2004 and 2005, new disease symptoms showing watery rot and soft rot were observed. In this study, the disease causal agents were identified as Geotrichum candidum, and their host range and pathogenicity were investigated. G. candidum isolated had wide host range and strong pathogenicity against carrot, cucumber, tomato and pumpkin. The disease occurrence on several vegetables that G. candidum can be a serious threat to stable production of fresh vegetable.

• Research in Plant Disease
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• v.8 no.3
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• pp.189-192
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• 2002

Mummy disease has been observed for a long time in the button mushroom, Agaricus bisporus farms in Korea, and severe mummy disease occurred on “Shinryung” mushroom, A. blazei recently. Typical symptoms of mummy disease were observed on the mushroom-cultivation beds infected ; tilted caps of mushrooms, browning and lignified internal tissue of stipe, overdevelopment of mycelium around the base of the stipe, and mummified mushrooms. Electron micrographs prepared from internal tissue of stripe of the diseased mushrooms showed that many bacterial cells present inside hyphal cells of the diseased mushroom, which is one of the characteristics of mummy disease reported previously, Survey in Buyo, Chungnam showed that mummy disease occurred at 55% and 83% frequency on bottom mushroom (brown strain) and “Shinryung” mushroom cultivation during year 2000. It indicates that mummy disease is one of the major diseases for the mushrooms cultivation.

• Research in Plant Disease
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• v.18 no.4
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• pp.402-405
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• 2012

We surveyed the occurrence of Rice stripe virus (RSV) disease in 672 fields from 29 rice representative area in July 2012 as nationwide survey for RSV occurrence since 2008. We confirmed occurrence of virus disease in 18 areas, in west coast region including Secheon, Taean, Buwan and Cheorwon. RSV incidence rates of plant in Sacheon and Buan were less than 0.01% and 0.15%, respectively, showing similar rate with the nationwide survey carried out in 2008, whereas incidence rate of field declined from 19.9% in 2008 to 4.9% in 2012. Earlier, RSV occurred largely across the southern region of Korea. In 2001, RSV disease was found in Gangwha and Gyeonggi-do, the northern region of Korea. In 2007, RSV appeared in west coast; Buan in Jeollabuk-do and Seocheon in Choongnam-do. After migration of the vector, small brown plant hopper, from China in 2009, RSV is becoming a pandemic.