• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.231-236
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• 1996

한국에서 재배되고 있는 벼 품종의 도열별에 대한 지속저항성 품종을 조기에 선발, 보급할 수 있는 방법을 보색하기 위하여 1985년부터 1994년까지 온실 유묘검정, 밭못자리 및 포장검정을 통하여 저항성 정도를 평가하고 재배면적과 재배기간을 참고로 하여 지속저항성 품종을 선발하였다. 도열병에 대한 저항성 품종으로는 다양한 레이스에 침해되면서 개체당 병반수 20개 이내, 밭못자리검정에서는 평균 발병정도 5이하, 본답에서의 잎도열병은 병반면적율 0.5%이하, 이삭도열병 발생은 이병수율 5% 이내로 병발생이 비교적 적은 섬진벼, 팔공벼 및 동진벼를 선발하였고, 지속저항성 품종으로는 재배기간이 10년 이상 유지되면서 재배면적은 전체재배 면적의 20% 이상을 차지하고 있는 품종 중 장기간 동안 저항성을 발현하는 동진벼를 선발하였다.

• Korean journal of applied entomology
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• v.21 no.2 s.51
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• pp.73-77
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• 1982

This experiment was carried out to study the effect of boron application on the physiological response and the outbreak of Granville wilt flue-cured tobacco. NC2326 and Coker 86(flue-cured tobacco) were transplante dand investigated in all field culture plots for this experiment. Elongation of shoots were retarded, and stem heights were shortened in all boron applied plots and the more boron applied, the greater these tendency was. The ratio of root branching and root discoloration, and contraction by Granville wilt were docreased markedly in boron plots. Amount of harvested loaves (yield) was increased greatly in 2 and 4kg plots of borax and boric acid per 10a, and the increasing tendency was greater in NC2326 variety than Coker 86. Phenol compounds content in harvested leaves were higher in boron applied plots than non-applied, and was higher in Coker 86, Granville wilt resistant variety, than NC2326. The more boron applied, the higher nicotine content in the harvested leaves was.

• Food Science and Preservation
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• v.23 no.6
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• pp.772-777
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• 2016

Activity of the noncontacted low temperature atmospheric pressure surface discharged plasma (LASDP) converts stable gas to ionized gas known as discharge or plasma. This ionized gas exhibits the antimicrobial activity. We examined the effects of 3 different storage treatments for 80 days on 'Setoka' : ambient storage (AS), low-tempperature storage (LTS), and low-temperature atmospheric pressure plasma+low-tempperature storage (PLTS). Total soluble solids showed no the significant differences between the 3 treatments. Acidity gradually decreased, and was 0.5% under AS after 30 days of storage. Fruit firmness increased by a few percent until 40 days of storage. Weight loss in AS was higher than for other treatments. After 80 days of storage, the decay ratio was significantly low in PLTS treatment: (AS, 50.5%; LTS, 5.6%; PLTS, 1.9%). In AS treatment, 73% of the rotten fruits were infected particularly with green and blue mold; however, only 1% of the rotten fruits were infected in case of PLTS treatment. In conclusion, LASDP treatment can prevent postharvest decay caused by fungi and is an efficacious alternative extending the shelf-life of citrus fruits.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.657-665
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• 2013

A large patch disease caused by Rhizoctonia solani AG2-2 (IV) is a serious problem in Korean lawngrass (Zoysia japonica) sites including golf courses and sports fields in Korea. Antagonistic microorganisms against R. solani AG2-2 (IV) were isolated from various forest and crop soil sources in Southern Korea. Among the 61 isolates, I-009, FRIN-001-1, and YPIN-022 strains showing dramatic inhibition of the mycelial growth of R. solani AG2-2 (IV) in the pairing culture were selected as the most potential antagonistic microorganisms for this study. Based on the 16s RNA sequence comparison, I-009 and FRIN-001-1 isolates were identified as Bacillus spp., while YPIN-022 isolate belongs to the genus Pseudomonas. The greater inhibition (clear) zone between two edges of the selected and pathogenic microbes ranged from 11 to 15 mm in three selections, but the others averaged to 7 mm out of 30 mm distance. In another antifungal test using culture filtrate, those three isolates represented a range of 51.7 to 63.5% suppression potential. The selected isolates also inhibited significantly the stem-segment colonization by R. solani AG2-2 (IV) in vivo test by 28.1%, 43.0%, and 23.7% when inoculated with I-009, FRIN-001-1, and YPIN-022, respectively. The highest antagonistic activity for the large patch disease was demonstrated by the isolate FRIN-001-1, which will be useful for developing a bio-pesticide against Rhizoctonia.

• Research in Plant Disease
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• v.9 no.1
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• pp.52-56
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• 2003

It was conducted to investigate the effect of rice downy mildew (RDM) infection to plant growth and yield components in water seeding stage, and to screen of varietal resistance to downy mildew. Being infected by rice downy mildew, chlorotic spot appeared in the leaf and leaf length was shortened. As the infected rice was growing, internode was not elongated properly and was deformed, and then panicle was not arised or mal-formed. Plant height of infected rice was shortened at all growth stage, and while the number of tillers of infected rice was more decreased than that of healthy plant before maximum tillering stage, and that of infected rice was more increased after heading stage. While the number of internode of infected tiller was much increased than that of healthy tiller internode length of infected tiller was shorter. As the rice infected by RDM severely, the number of panicles per square meter and ripening of rice was more decreased and yield of rice was extremely much decreased. As result of the varietal resistance screening with rice seedling, Geyh-wabyeo and Donjinbyeo were resistant varieties to downy mildew.

• Journal of fish pathology
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• v.25 no.3
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• pp.271-277
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• 2012

The practical monitoring was performed to survey the mortalities in aquaculture farms of olive flounder, rockfish, rainbow trout, Japanese eel, white shrimp and abalone in South Korea from May to November, 2011. The aquatic organism disease inspectors, who have the national licenses for the diagnosis and prevention of aquatic disease and have close relationship with the farms, investigated the rates and causes of mortalities according to the standard manual. In 70 flounder farms, the cumulative mortalities rate was 27.9%, and the mortalities were caused by scuticociliatosis, streptococcosis, VHS, non-infectious loss, vibriosis and gliding bacterial disease. The moralities rate of 30 rockfish farms was 13.6%, and those were mainly contributed by gill flukes and streptococcosis. Most of mortalities of rainbow trout were caused by non-infectious loss and protozoan white spot disease. The mortalities rate of Japanese eel was 0.6% by edwardsiellosis, protozoan white spot disease and gill flukes. The loss rate of white shrimp was 71.2%, and most of them was related with non-infectious ones, such as carnivalization, transportation loss, and the rest was caused by viral white spot disease. The mortalities rate in the abalone farms was 10.7% and all of them were related with non-infectious loss.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.4
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• pp.417-420
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• 2008

This study was carried out to compare the growth and yield characteristics between bakanae diseases (Gibberella fujikuroi) infected and uninfected rice plants with different disinfection mothods. The infected rice seeds, harvested previous year, were disinfected either with prochloraz for 48 hours at $33^{\circ}C$ in germinator or 24 hours at room temperature and not disinfected. In the methods of disinfection, it is more effective in disinfected by prochloraz for 48 hours at $33^{\circ}C$ using germinator near to 0% of infection rate, followed by conventional method as 5.0% and 76% in not disinfected rice seeds. In the rice yield components among the disinfection methods, panicles were increased about 11% in the disinfected seeds using germinator for 48 hours compared to conventional method. Ripening grain rate also increased at the disinfected using germinator as $80.3{\sim}80.3%$, improved more than $4.9{\sim}5.9%$ compared to the conventional disinfection. From these results, the rice yield was $512{\sim}517\;kg/1,000\;m^2$ at the disinfected using germinator which increased more than $6{\sim}7%$ compared to the conventional disinfection.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.156-161
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• 1986

Silage productivity and resistance to rice black streaked dwarf virus (RSDV) of six Korean-improved and six US introduced corn genotypes were tested in the southern part of Korea. There was a negative correlation between culm length retarded by RBSDV and coefficients of variance of culm length. Frequency distribution of culm length could be classified as three genotypic groups according to the type of distribution and percentage of RBSDV diseased plants. There were negative correlations between percent RBSDV diseased plants at harvest and culm length, percent ear bearing plants, silage yield, or ear yield, but percent RBSDV diseased plants did not related to the ear/silage ratio and stover yield. Silage yield of Pioneer XCF38 was highest, but that of Suweon 89 and NC 6131 was lowest. However, there was not signi-ficant difference in silage yield among the remaining genotypes. Pioneer XCF38, Suweon 89, and Jinjuok were quite resistant to RBSDV, but Suweon 19, Kwangok, Hoengseongok, Jecheonok, and Pioneer 3424 were susceptible and NC 6131 was most susceptible to RBSDV. Although Jinjuok and Suweon 89 were resistant to RBSDV, silage yield was not high because of early senescence of leaves after silkillg.

• Research in Plant Disease
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• v.24 no.2
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• pp.145-152
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• 2018

During 2015-2017, we surveyed the incidence of viral infections of tomato and paprika growing in greenhouses in Cherwon province, Korea. In 2015 and 2016, we collected leaves and fruits from tomato and paprika plants growing in greenhouses. We detected viruses in the samples collected using specific primer sets for Broad bean wilt virus 2 (BBWV2), Cucumber mosaic virus (CMV), Pepper mild mottle virus (PMMoV), Pepper mottle mosaic virus (PepMoV), and Tomato spotted wilt virus (TSWV). We detected PMMoV, CMV, and TSWV in the samples, and CMV and TSWV were the most prevalent. For the prevention of future viral diseases, we then surveyed the routes of infection by these viruses in tomato and paprika plants growing in greenhouses in Cherwon province in 2017. Leaf and fruit samples were collected from seedlings and crops two and four months after transplanting into greenhouses. As a result, we found that TSWV was transferred from seedlings to plants, and outbreaks of the virus occurred at the early stage of cultivation. On the other hand, we found that CMV was a virus indigenous to the soil of some towns in Cherwon province, and thus outbreaks of this virus occurred at the middle stage of cultivation.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.139-144
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• 2006

Chestnut trees have been severely damaged by the various cankers in Korea. Field surveys for elucidating the relationships between disease occurrence and environmental factors, i.e., tree age, temperature, rainfall precipitation, direction, degree of slope, chemical properties of soils, and so on, were carried out in the chestnut tree plantations located at Gyeongnam, Jeonnam, Chungnam, and Gyeonggi-Do Province. Totally, one thousand and one hundred thirty seven trees from 36 experiment plots were investigated. Trees infected by at least one of the canker fungi were estimated up to 66%. The most severely infested area was Sunchon in Jeonnam Province with the rate of 80%, while the most lightly infested area was Kongju in Chungnam Province with 39%. Disease occurrence was found to be highly correlated with tree age. The disease occurred most frequently on trees ranged from 7 to 12 years old, while it was relatively low on trees below 5 years old or above 25 years old. Canker positions on the tree formed by the pathogenic fungi were most often at 1.6-2.0m above the ground. Over five hundreds bark samples from the canker area on the tree were collected and the pathogenic fungi were isolated. The most commonly isolated fungus was identified as Cryphonectria parasitica, the chestnut blight fungus.