• Title/Summary/Keyword: Black Spot

Search Result 186, Processing Time 0.026 seconds

Comparing the Effectiveness of Road Safety Features by Spatial Scope of Safety Improvement Project (도로안전개선사업의 공간적 범위에 따른 도로안전시설물의 효과도 비교)

  • Park, Gyu-Yeong;Kim, Tae-Hui;Kim, Seong-Uk;Lee, Su-Beom
    • Journal of Korean Society of Transportation
    • /
    • v.24 no.4 s.90
    • /
    • pp.31-42
    • /
    • 2006
  • The purpose of this study is to compare the effectiveness of road safety features by spatial scope Spot & Section-based safety Improvement project. Empirical data was collected from black-spot study of Jeonbuk and "Traffic Safety Improvement Project on National Highway 17". Evaluation model of effectiveness was developed by using Empirical Bayes (EB) method. And Relative Effectiveness was measured by Odds Ratio. The result indicates that Section-based safety improvement was $7.09{\sim}77.27%$ more effective than the spot-based. It means that section-based improvement projects should be expanded while considering the characteristics of the section in spot based improvement.

Leaf Spot of Broad Bean (Vicia faba) Caused by Alternaria tenuissima (Alternaria tenuissima에 의한 잠두 점무늬병)

  • Kwon, Jin-Hyeuk;Park, Chang-Seuk
    • Research in Plant Disease
    • /
    • v.8 no.2
    • /
    • pp.117-119
    • /
    • 2002
  • Leaf spot disease was found on broad bean (vicia faba) in several farmer's fields located in Changseon-myon, Namhae-gun, Gyeongnam province, Korea. The typical symptoms of the disease were appeared on leaves, stems and pods. The infection rates of the disease in the surveyed area were ranged from 8.4 to 46.8%. Colonies formed on PDA were developed aerial hyphae with grayish white, which later turned olive-green to black. Conidia were dark brown in color, long ellipsoid to elongated ovoid, obclavate and 23.7~61.3$\times$7.2~16.8 ${\mu}{\textrm}{m}$ in size. Septa were 4~10 transvers, 1~2 longitudinal or oblique. Conidiophores were solitary or fascicles and 18~113$\times$3~6 ${\mu}{\textrm}{m}$ in size. The optimum temperature for growth of the fungus was about 3$0^{\circ}C$. This is the first report on the leaf spot of broad bean caused by Alternaria tenuissima in Korea.

Inter-comparison of Two Aethalometers for Aerosol Black Carbon Measurements (대기 에어로졸 검댕입자 측정을 위한 두 aethalometer의 상호비교)

  • Jung, Jung-Hoon;Park, Seung-Shik;Yoon, Kwan-Hoon;Cho, Sung-Yong;Kim, Seung-Jai
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.27 no.2
    • /
    • pp.201-208
    • /
    • 2011
  • Recently, a real-time, pocket-sized aethalometer (microAeth$^{(R)}$ model AE51) has been developed by Magee Scientific Inc. for measuring the concentration of black carbon in the atmosphere. In this study, two aethalometers, models AE-16 and AE-51, which measure the optical absorption of carbon particles at infrared 880 nm, were operated at time interval of 5-min between January 9 and February 10, 2010 at an urban site of Gwangju, to compare the accuracy of black carbon (BC) concentrations reported from the AE-51 model and to investigate reasonable sampling time of filter media in the AE-51. The air samples in the AE-51 and AE-16 models are collected on T60 (Teflon coated glass fiber) filter media (filter spot area: 0.07 $cm^2$) and quartz fiber roll-tape filter (filter spot area: 1.67 $cm^2$), respectively. Real-time measurement results indicate that when the filters were clean, the AE-51 BC was greater than or similar to the AE-16 BC data. However as the filter spots become darker, the AE-16 BC concentrations were higher than the AE-51 BC data and the difference in the BC concentrations from two AE models becomes gradually increased. Relative error in the AE-51 and AE-16 BC concentrations showed significance difference depending on used time of the filter in the AE-51 model, weather pattern, levels of air pollution, etc, ranging from 11.5% (used time of the filter in AE-51: 1,595 min) to 52.5% (used time of the filter in AE-51: 2,085 min). When considering the used time of one filter ticket in the AE-51 model and difference (or relative error %) between AE-16 and AE-51 BC concentrations, it is recommended that the standard sampling time per one filter ticket within the AE-51 model be less than approximately 24 hr (1,440 min) under the normal weather conditions except for severe haze and mist events.

Effects of Weed Control on Pseudocercospora vitis and Fruit Characteristics in Campbell Early Vineyard (캠벨얼리 포도원에서 잡초관리 방법이 갈색무늬병 및 과실특성에 미치는 영향)

  • Kim, Sun-Kook;Choi, Won-Ho;Lee, Seok-Ho;Lee, Yun-Sang;Yoon, Changmann;Hong, Seong-Tac
    • Korean Journal of Organic Agriculture
    • /
    • v.23 no.4
    • /
    • pp.897-909
    • /
    • 2015
  • This study was conducted to evaluate the effect of weed control on disease incidence, plant growth and fruit quality, and to provide effective method to farmers at the vineyard. At the raincoat greenhouse cultivating 'Campbell Early', several weed controlling methods were compared to the control. Mean temperature of plots between soil covering (C.B., W.F., S.N., P.F. and R.H.) and non soil covering (M.W.2, M.W.3 and U.T.) were similar with $26.2^{\circ}C$ (July) and $25.8^{\circ}C$ (Aug.), but humidity of soil covering was sharply decreased in late-July under 40%. Soil water were all higher in soil covering plots than that of non-soil covering, however, soil temperature was recorded lower in soil covering plots. Disease incidence of Peudocercospora vitis according to soil coverings had effect on black plastic film mulching by decreasing grapevine leaf spot to 85% in July, 69% in August, compared to the control, with showing the smallest lesion incidence in FMB. Among growth characters, internode length and internode width of black plastic film mulching was higher than that of the control. SPAD value of black plastic film mulching was recorded the highest. It was not significant among the treatments, but brix was recorded highly in black plastic film mulching with $14{\sim}15^{\circ}Brix$.

Ecopathological Analysis of Apple stem grooving virus-K Harboring Talaromyces flavus

  • Shim Hye-Kyung;Hwang Kyu-Hyon;Shim Chang-Ki;Hong Seung-Beom;Son Su-Wan;Kim Dong-Giun;Choi Yong-Mun;Chung Young-Jae;Kim Dae-Hyun;Jee Hyeong-Jin;Lee Suk-Chan
    • The Plant Pathology Journal
    • /
    • v.22 no.3
    • /
    • pp.248-254
    • /
    • 2006
  • Pear black necrotic leaf spot (PBNLS) on pear trees (Pyrus pyrifolia) is caused by a Korean isolate of Apple stem grooving virus (ASGV-K). Yellow spots were detected in Phaseolus vulgaris (kidney bean) and Chenopodium quinoa which were grown near the diseased pears in year 2000 through 2003. The ASGV-K, the causative agent of PBNLS, was detected from the symptoms of the diseased kidney bean plant and C. quinoa. ASGV-harboring fungi were also isolated from symptomatic plants and from soils surrounding the infected plants. The ASGV-harboring fungus was identified and characterized as Talaromyces flavus. Ecopathological studies showed that the number of ASGV-harboring fungi on the pear leaves was not correlated with differences in temperature or severity of symptoms. Additionally, there was no difference in fungus frequency among the orchard locations or different host plants. Although the frequency of fungi isolated from the soil was not affected by changes in temperature or location, the fungi occurred at higher densities in the rhizosphere than in the plants themselves.

The Pear Black Necrotic Leaf Spot Disease Virus Transmitted by Talaromyces flavus Displays Pathogenicity Similar to Apple stem grooving virus Strains

  • Shim Hye-Kyung;Hwang Kyu-Hyon;Shim Chang-Ki;Son Su-Wan;Kim Dong-Giun;Choi Yong-Mun;Chung Young-Jae;Kim Dae-Hyun;Jee Hyeong-Jin;Lee Suk-Chan
    • The Plant Pathology Journal
    • /
    • v.22 no.3
    • /
    • pp.255-259
    • /
    • 2006
  • The pathogenicity to pear trees and other experimental hosts of the Apple stem grooving virus Korean isolate (ASGV-K) carried by a fungal vector, Talaromyces flavus was examined. ASGV-harboring T. flavus induced mild symptoms on virus-free pears. Symptom severity was intermediate between pears showing typical PBNLS and virus-free pears. Ten cultivars of Phaseolus vulgaris showed 35%-90% infectivity by direct infiltration into leaves and roots by ASGV-harboring T. flavus. Application of fungal cultures to soils showed 0%-70% infectivity depending on the P. vulgaris cultivar. Sap extracted from ASGV-infected Chenopodium quinoa induced similar symptoms on P. vulgaris at 25 days after inoculation. Similar symptoms were also detected on P. vulgaris which were inoculated with ASGV-harboring T.flavus. When healthy P. vulgaris leaves were challenged with sap extracted from P. vulgaris leaves infected with ASGV-harboring T. flavus, typical symptoms were observed. These data suggest that T. flavus mediates the transfer of ASGV to host plants.

Highly Specific Detection of Five Exotic Quarantine Plant Viruses using RT-PCR

  • Choi, Hoseong;Cho, Won Kyong;Yu, Jisuk;Lee, Jong-Seung;Kim, Kook-Hyung
    • The Plant Pathology Journal
    • /
    • v.29 no.1
    • /
    • pp.99-104
    • /
    • 2013
  • To detect five plant viruses (Beet black scorch virus, Beet necrotic yellow vein virus, Eggplant mottled dwarf virus, Pelargonium zonate spot virus, and Rice yellow mottle virus) for quarantine purposes, we designed 15 RT-PCR primer sets. Primer design was based on the nucleotide sequence of the coat protein gene, which is highly conserved within species. All but one primer set successfully amplified the targets, and gradient PCRs indicated that the optimal temperature for the 14 useful primer sets was $51.9^{\circ}C$. Some primer sets worked well regardless of annealing temperature while others required a very specific annealing temperature. A primer specificity test using plant total RNAs and cDNAs of other plant virus-infected samples demonstrated that the designed primer sets were highly specific and generated reproducible results. The newly developed RT-PCR primer sets would be useful for quarantine inspections aimed at preventing the entry of exotic plant viruses into Korea.

Occurrence of Target Spot on Rosemary Caused by Corynespora cassiicola in Korea (Corynespora cassiicola에 의한 로즈마리 점무늬병)

  • Lee, Wang-Hyu;Han, Sang-Jun;Choi, In-Young
    • Research in Plant Disease
    • /
    • v.19 no.1
    • /
    • pp.55-59
    • /
    • 2013
  • The purpose of this experiment was to investigate the development of new spot disease on the leaf and stem of rosemary (Rosmarinus officinalis) in commercial greenhouses at Jeonju and Namwon in Korea. Incidence of target spot on rosemary was higher at the end of the rainy season with high humidity. Those symptoms were black ring spots (3-5 mm in diameter) and withering on green leaves and stems. Conidiophores and conidia were formed on the infected tissue in moist chamber and conidia were shown as the cylindrical and oval types in chain, ranged from 55 to $275{\mu}m$ in length, and 7 to $14{\mu}m$ in width. Conidia with eight to ten pseudosepta were formed on the conidiapore. The optimum growth temperature of isolates was $30^{\circ}C$ on the PDA medium under the dark condition. In the pathogenesis test, the target spot and withering symptoms were appeared on the leaves and stems 3 days after inoculation showing similar symptoms compared to those of in nature. The same fungus was re-isolated from infected lesion, indicating that Corynespora cassiicola caused leaf target spot and twig blight on rosemary. The rDNA ITS nucleotide sequences of the pure cultured isolate from the diseased area on rosemary showed 100% similarity to the sequences of C. cassiicola available in the GenBank database (JQ595296, JQ595297, FJ852715 and AY238606). Therefore, we report that the target spot of leaves and stems in rosemary was caused by C. cassiicola.

Antibacterial Activity of Crude Aronia melanocarpa (Black Chokeberry) Extracts against Bacillus cereus, Staphylococcus aureus, Cronobacter sakazakii, and Salmonella Enteritidis in Various Dairy Foods: Preliminary Study

  • Kim, Dong-Hyeon;Lim, Hyun-Woo;Kim, Se-Hyung;Lee, Jun-Man;Chon, Jung-Whan;Song, Kwang-Young;Bae, Dongryeoul;Kim, Jinhyun;Kim, Hyunsook;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
    • /
    • v.36 no.3
    • /
    • pp.155-163
    • /
    • 2018
  • In this study, the antibacterial activity of Aronia melanocarpa (black chokeberry) ethanol extract against Bacillus cereus, Staphylococcus aureus, Cronobacter sakazakii, and Salmonella Enteritidis was investigated using the spot-on-lawn assay. The results showed that this extract exhibited antibacterial activities against Bacillus cereus (complete inhibition) and Staphylococcus aureus (partial inhibition), but did not inhibit the growth of Cronobacter sakazakii and Salmonella Enteritidis. This study shows that the Aronia melanocarpa (black chokeberry) ethanol extract was more effective against Gram-positive bacteria than Gram-negative bacteria. Hence, it is suggested that Aronia melanocarpa could be a useful food supplement, and could be utilized as a naturally derived additive for maintaining the safety of various dairy products. Furthermore, future research should be conducted to examine the possibility of using such products as functional ingredients for improving the anti-oxidative and anti-inflammatory activities of food products.

Elucidation of Cause of Cotyledon Black-Decay of Soybean Sprout by Bean Bug, Riptortus clavatus

  • Lee, Jung-Han;Han, Ki-Soo;Kim, Dong-Kil;Kang, Jin-Ho;Kim, Hee-Kyu
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.53 no.3
    • /
    • pp.303-307
    • /
    • 2008
  • Cotyledon Black Decay (CBD) on soybean sprout mimics the black spot due to microbial infection. CBD, not visible or predictable at seedlot state, for some reason, shows up exclusively on cotyledon of soybean sprout during sprouting process. Such an incidence rate fluctuated from 0.8 to 19.5% over three years from 2004. We suspected some pod-infecting anthracnose fungi and/or pod-blight pathogen, or pod-sucking bean bug, one of the major pests of soybean, might have involved, of which we ruled out fungal pathogen because it was preventable through heat treatment, a proven method for seedlot disinfestation. The healthy seeds artificially fed by bean bug for one to seven days were sprouted, and 6 to 41% of the soybean sprout revealed the CBD mimic to those occurred in soybean sprout from previous commercial seedlot screening experiments. This finding is the first report to confirm that bean bug damage to pod at $R_8$ stage is directly responsible for the CBD, which did not concur with any other deleterious effects on sprouting such as reduction in hypocotyls elongation and rooting except unsightly sprout quality. However, earlier feeding either at green pod or greenish yellow pod stage ($R_6$ -early $R_7$ stage) resulted in rather severe damages, which strikingly reduced hypocotyls growth to about one forth to about two third, as well as the reduction in rates of seed germination.