• Journal of Ecology and Environment
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• v.34 no.2
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• pp.215-222
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• 2011

We evaluated the carbon (C) and nitrogen (N) status of litterfall in a natural red pine (Pinus densiflora) stand damaged by pine wilt disease in Jinju City, which was one of the areas severely affected by the disease in Korea. A significant correlation (P < 0.05) was found between tree density and basal area and the C and N status of litterfall components, but C and N status was not correlated with mean diameter at breast height in the pine wilt disease stands. Needle-litter C and N concentrations were linearly related (P < 0.05) to basal area in pine wilt disease stands. Needle-litter C concentration decreased with a decrease in damage intensity due to pine wilt disease, whereas litter N concentration increased with an increase of basal area in pine wilt disease stands. The linear regression equations developed for litterfall C and N inputs were significant (P < 0.05), with basal area accounting for 50-86% of the variation, except for cone and flower litter. The results indicated that the incidence of pine wilt disease could impact the quality and quantity of C and N in litterfall of pine stands suffering from pine wilt disease.

• Journal of Korean Society of Forest Science
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• v.108 no.3
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• pp.296-301
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• 2019

This study was conducted to measure litterfall and nutrient (P, K, Ca, Mg) inputs under varying degrees of disturbance by pine wilt disease in pine forests in southern Korea. Litterfall was collected to evaluate nutrient responses at different intensities of disturbance (various levels of basal area) by pine wilt disease across 2 years. Phosphorus, Ca, and Mg concentrations in needle litterfall were positively correlated (p < 0.05) with decreased disturbance intensities (increased basal area) depending on the time of sampling, whereas the nutrient concentrations in other litterfall components (branches, bark, reproductive organs, and miscellaneous litterfall) were not significantly correlated (p > 0.05) with the intensity of pine wilt disease disturbance. Dry weight and nutrient inputs through litterfall components decreased linearly with increasing intensity of disturbance by pine wilt disease (p < 0.05), except for the nutrient inputs of branch (K, Ca, Mg) and reproductive organ (K, Ca) litterfall. These results indicate that decreased litterfall across different levels of disturbance may be related to the reduced soil nutrients in pine wilt disease forests.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.3
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• pp.317-325
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• 2021

Pine wilt disease first appeared in Busan in 1998; it is a serious disease that causes enormous damage to pine trees. The Korean government enacted a special law on the control of pine wilt disease in 2005, which controls and prohibits the movement of pine trees in affected areas. However, existing forecasting and control methods have physical and economic challenges in reducing pine wilt disease that occurs simultaneously and radically in mountainous terrain. In this study, the authors present the use of a deep learning object recognition and prediction method based on visual materials using an unmanned aerial vehicle (UAV) to effectively detect trees suspected of being infected with pine wilt disease. In order to observe pine wilt disease, an orthomosaic was produced using image data acquired through aerial shots. As a result, 198 damaged trees were identified, while 84 damaged trees were identified in field surveys that excluded areas with inaccessible steep slopes and cliffs. Analysis using image segmentation (SegNet) and image detection (YOLOv2) obtained a performance value of 0.57 and 0.77, respectively.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.296-300
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• 2005

Among the root colonizing and plant growth promoting bacteria isolated from the bacterial wilt suppressive soil, five strains were detected to produce siderophores by CAS agar assay. The most effective isolate, TS3-7 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 80% reduction of bacterial wilt disease compared with the control. Significant disease suppression by TS3-7 strain was related to the production of siderophore. Besides iron competition, induction of resistance of the host plant with siderophore was suggested to be another mode of action that suppress bacterial wilt, based on the lack of direct antibiosis against pathogen in vitro. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, TS3-7 stain was identified as Pseudomonas sp. TS3-7.

• Journal of Environmental Science International
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• v.25 no.1
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• pp.127-134
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• 2016

This study is conducted to get current state of data collection and utilization of the trees damaged by pine wilt disease, and to efficiently collect and utilize of the trees damaged by the pine wilt disease and abandoned fumigation-treated trees at forecasts. The method to control pine wilt disease damaged area is mostly fumigation treatment system, and there is no collection and utilization of damaged trees because of absence of efficient collection system, lack of collection cost, and absence of policy, etc. A survey is conducted that asked about the satisfaction degree for the trees damaged by pine wilt disease collection and use divided into 6 topics. It was positively recognized that the need and problem of the trees damaged by pine wilt disease, and results and satisfaction of forestry mechanization while it was mostly negatively recognized that the policy satisfaction for prevention and collection, satisfaction of collection and use, collection and forestry mechanization, and satisfaction of foundation equipment for forestry mechanization, etc. As a result of path analysis, it is necessary to promote a high-tech forestry mechanization to improve satisfaction level of results and satisfaction of forestry mechanization for the trees damaged by pine wilt disease collection and utilization, it is also need to make an effort in various ways for improve satisfaction level of satisfaction of collection and utilization.

• The Plant Pathology Journal
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• v.18 no.5
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• pp.279-283
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• 2002

Biological control of Fusarium udum causing wilt disease of pigeonpea was studied in vitro, as well as, in vivo. Aspergilluspavus, Anergillus niger, Bacilius licheniformis (strain-2042), Gliocladium virens, Peniciliium citrimum, and Trichoderma harzianum, which were found to be the most potent ones in inhibiting the radial colony growth of the test pathogen, were used as biological control by amending their inocula at diffeyent concentrations in pots and in pathogen-infested soil in the fields. Maximum reduction of the wilt disease was observed with G. vireos both in pots and in the fields. The population of E. udum was found to be markedly reduced when the antagonists were applied in the soil. The study establishes that G. virens can be exploited for the biological control of wilt disease at field level.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.113-117
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• 2006

Occurrence of the oak wilt disease (Raffaelea sp.) was confirmed in 2004 for the first time in Korea. By using pictorial keys, morphological characteristics of Platypus koryoensis (Murayama), a vector for this disease in Korea, was compared to Platypus quercivorus (Murayama), a vector of oak wilt in Japan. Additionally, suggestions were made for the future research of the vector of oak wilt disease in the northeastern Asia.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.263-269
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• 2009

Bacterial wilt, Fusarium wilt and Foot rot caused by Ralstonia solanacearum, Fusarium oxysporum, and Phytophthora capsici respectively, continue to be severe problems to tomato, potato and black pepper growers in Vietnam. Three bio-products, Bacillus vallismortis EXTN-1 (EXTN-1), Bacillus sp. and Paenibacillus sp. (ESSC) and Bacillus substilis (MFMF) were examined in greenhouse bioassay for the ability to reduce bacterial wilt, fusarium wilt and foot rot disease severity. While these bio-products significantly reduced disease severities, EXTN-1 was the most effective, providing a mean level of disease reduction 80.0 to 90.0% against bacterial wilt, fusarium wilt and foot rot diseases under greenhouse conditions. ESSC and MFMF also significantly reduced fusarium wilt, bacterial wilt and foot rot severity under greenhouse conditions. Bio-product, EXTN-1 with the greatest efficacy under greenhouse condition was tested for the ability to reduce bacterial wilt, fusarium wilt and foot rot under field condition at Song Phuong and Thuong Tin locations in Ha Tay province, Vietnam. Under field condition, EXTN-1 provided a mean level of disease reduction more than 45.0% against all three diseases compared to water treated control. Besides, EXTN-1 treatment increased the yield in tomato fruits 17.3% than water treated control plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.5
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• pp.35-53
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• 2021

A field survey was carried out targeting 59 pine wilt disease control areas distributed in Andong, and the ecological characteristics of the areas affected by pine wilt disease were analyzed using vegetation information, ecological information, and land use information. Vegetation characteristics of Pine wilt disease affected forest area showed a 3-layer vegetation structure, high percentage of accidental occurrence species (37%) and secondary vegetation species (59.6%), appearing 12 taxa naturalized plants and 3 taxa ecosystem disturbance organisms designated by the Ministry of Environment. Ecological information of Pine wilt affected area showed frequent occurrence of water stress in south and west slopes, low lying grounds in mountains, and in well-drained soils. Also, surrounding the area has been used as roads, tombs, and cultivation where intensive human activities were the cause of disturbance and stress to the pine forest. It was analyzed that the pine forest in Andong city suffered extensive damage due to the onset of pine wilt disease while the pine trees were weakened due to continuous human activities. Conclusively, the spread and onset of pine wilt disease are worsened by artificial factors than natural environmental conditions.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.198-202
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• 2010

A study was conducted to find out the relationship of physico-chemical properties (viz. organic carbon(OC), pH, electrical conductivity, nitrogen, phosphorus and potassium content) of ginger growing soil with incidence percentage of rhizome rot and wilt disease complex of ginger. Organic carbon content and pH of the ginger soil contributed significantly (93%) in the prediction of ginger rhizome rot and wilt disease complex incidence with negative correlation. Soil having weak acidic reaction with OC percent greater than 2.25 was observed to have the lower average incidence of the disease.