• Research in Plant Disease
• /
• v.16 no.1
• /
• pp.86-89
• /
• 2010

Brown leaf spot caused by Phyllosticta cruenta from 2007 to 2009 occurred severely in an herbs exhibition on Doonggulle (Polygonatum odoratum) at Gangju pond in Jeongchon-myon, Jinju city, Gyeongnam province, Korea. The typical symptoms of this disease were appeared on the brown leaf spot of leaves. Lesions on the leaves were appeared elliptical or irregular with 2~8 mm in size. Infected leaves were wilted, blighted and eventually died. Pycnidiospores and pycnidia of the fungus were abundantly formed on PDA. The optimum temperature for mycelial growth was $20{\sim}{25^{\circ}C}$. Pycnidiospores were not readily formed on PDA, colorless in color, globose~subglobose in shape, $10{\sim}18{\times}5{\sim}12{\mu}m$ in size and appendage hanged $4{\sim}15{\mu}m$ in size. Pycnidia were globose~subglobose in shape, dark brown in color and $60{\sim}162{\times}70{\sim}174{\mu}m$ in size. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Phyllosticta cruenta (Kunze: Fries) Kickx. This is the first report on the brown leaf spot of Doonggulle caused by P. cruenta in Korea.

• Korean Journal Plant Pathology
• /
• v.14 no.6
• /
• pp.668-675
• /
• 1998

These surveys were conducted to check the occurrence of disease in various horticultural crops in alpine areas, especially Daekwallyong areas, Pyongchang-Gun, and Hyeongseong-Gun in Kangwon province. TuMV on Chinese cabbage was one of the most serious diseases, especially in 1994 and 1997. The incidence of soft rot and clubroot has been increased gradually. Brittle root rot on Chinese cabbage was significantly decreased. Soft rot, gray mold, downy mildew, powdery mildew, bottom rot and Alternaria leaf spot were the common diseases on most vegetable crops. Gray mold (Botrytis cinerea) on celery, cercospora leaf spot (Cercospora sp.) on melon, powdery mildew (Erysiphe cichoracearum) on lettuce, and clubroot (Plasmodiophora brassicae) on parsley are newly found in Korea. The most common and predominant diseases were viruses, especially CMV, TMV, TuMV, BBMV, and gray mold, wilts, and cercospora leaf spot on many flowers in alpine areas. Fusarium oxysporum f. sp. eustomae causing wilting on lisianthus (Eustoma grandiflorum), Turnip mosaic virus causing mosaic and color breaking on stock, Cercospora spp. causing cercospora leaf spot on various wild lily, Cladosporum echinulatum causing leaf spot on carnation, and phytoplasma causing witches' broom on statice (Limonium sinuatum) and blazing star (Liatris spp.) were newly found during these surveys in Korea.

• Research in Plant Disease
• /
• v.21 no.3
• /
• pp.243-249
• /
• 2015

Soybean frogeye leaf spot caused by the fungus Cercospora sojina Hara, has known to lead a severe reduction of crop yield. Since frogeye leaf spot on soybean has recently become a serious problem in Korea, the susceptibility of recent recommended cultivars against C. sojina had been tested. To standardize the disease severity of soybean, the optimum sporulation condition of C. sojina and the disease index were established in this study. Sporulation was maximized on the 10% V8 juice agar with 12 h light and 12 h dark at $25^{\circ}C$. Spore suspension ($10^5spores/ml$) was sprayed on the leaves of soybean (V6 stage), and the disease responses to each isolate were evaluated on 28 days after inoculation. As a result, Daepung, Shinpaldal2ho, Yeonpung and Cheonga showed the resistance reaction to 8, 7, 6, 6 isolates of C. sojina, respectively, whereas Cheongja, Hwangkeum, Taekwang, Daewon, Cheonsang and Sinhwa showed the susceptible reaction to 8 isolates of C. sojina. Breeding the resistant soybean cultivars against C. sojina requires a uniform resistance for screening technique. The disease index of frogeye leaf spot on soybean developed in this study can be effectively used for the accurate field assay to select the frogeye leaf spot resistant soybean.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 1999.10a
• /
• pp.61.1-61
• /
• 1999

• Research in Plant Disease
• /
• v.17 no.2
• /
• pp.228-231
• /
• 2011

Since 2008, a new leaf spot disease has been found in loquat tree (Eriobotrya japonica) at a nursery station in Goheung, Korea. Above 50% of the seedlings developed the spot symptoms on the leaves. The infected plants were generally reduced in the seedling vigour and early defoliation was occurred. The infected leaves developed grayish lesion with dark reddish brown margin. The pathogen developed round to ellipsoidal acervuli on the lesion. Based on morphological characteristics of the pathogen, the fungus was identified as Entomosporium mespili. The cultured pathogen successfully reproduced the same disease symptom on the leaves of loquat tree and found to be E. mespili. A monoconidial culture was deposited in Korean Agricultural Culture Collection (KACC 44727). This is the first report of E. mespili causing leaf spot of loquat tree in Korea.

• 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.

• Korean journal of applied entomology
• /
• v.26 no.4 s.73
• /
• pp.245-249
• /
• 1987

In the 82 apple varieties tested, the distribution of varieties grouped on the damage degree to Alternaria leaf spot were 15 varieties(l8.3%), which damaged above 50%, and 51 varieties(62.2%) damaged below 5%. Susceptible varieties to Alternaria leaf spot were Raritan, Indo, Winesap and Starkrimson, moderately resistant varieties Sekaiichi and Starking, and resistant Jonathan, Tsugaru, Molliies, Jonagold, Gala etc. The leaf hair density on the backside of leaf were rarer inresistant varieties than susceptible one. In inoculation test, penetration and infection of Alternaria mali were easier on the backside than surface of apple leaf at the same varity, and infection rate with Alternaria mali were higher at removal treatment than non-removal one of leaf hairs, so we can guess that leaf hair are related to resistance of variety to Alternaria mali.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.1
• /
• pp.239-246
• /
• 2013

The purpose of this study was to find out the potential of the Mosidae(Adenophora remtriflora) leaf, one of the natural ingredients, for the cosmetics by measuring their antioxidant functions and skin improving effects. The result of the phytonutrient of the Mosidae leaf test shows, that the heat extract of Mosidae leaf DPPH has 9% higher ability than Ethanol extract.(p<0.05), but significant a difference was not found between the hydroxyl Radical of Mosidae leaf heat extract (65.22%) and Ethanol extract(63.50%). Mosidae leaf heat extract(40.82mg/mL) has much lower polyphenol compound than Ethanol extract(47.90mg/mL)(p<0.05). A clinical test of Mosidae leaf powder pack was performed for a group of 16 middle aged women(age between 35-60) from October 20 to November 17, 2011. Control group was used on the right cheek, and test group was used on left cheek for comparison. The procedure was twice a week for 4 weeks to identify and grade level of moisture, roughness, pore size and spot. After 4 weeks of testing, there were significant improvements in moisture enhancement and spot(p<0.05), subtle change in roughness and the size of the pores. Therefore, we confirmed skin improvement effect of Mosidae leaf as new cosmetic material.

• Research in Plant Disease
• /
• v.9 no.3
• /
• pp.162-165
• /
• 2003

High sporulation method and cultural characteristics of Cercospora capsici causing Cercospora leaf spot of pepper were examined. Optimum temperature for mycelial growth of Cercospora capsici was $25^{\circ}C$. The fungus did not grow below $5^{\circ}C$ and over $35^{\circ}C$. Optimum pH for mycelial growth was pH 4.0~pH 8.0. Mycelial growth was not influenced by light. C. capsici sporulated well on pepper leaf agar (5g/l). A standard method of sporulation established was as follows. The mycelial plugs were ground with some water in motar with pestle. The mycelial suspension was smeared on the surface of medium and incubated for 2~3 days at $20^{\circ}C$. The culture surface was lightly scraped with a brush after adding 1 ml of sterile water to stimulate sporulation and further incubated for 2~3 days.

• Research in Plant Disease
• /
• v.10 no.2
• /
• pp.121-125
• /
• 2004

An epidemic of target leaf spot of cucumber (Cucumis sativus) occurred in commercial greenhouses in Korea in 2000/2001. The early symptoms on the leaves were small brown spots with yellow halos. These lesions became irregular enlarging in diameter and eventually defoliation resulted. The causal agent was a fungus with morphological characteristics matching Corynespora cassiicola. The sequence of the ITS region of C. cassiicola CM2000-1 was identical to that of an authentic strain of Corynespora cassiicola. Optimal germination of spores and mycelial growth on plate was at 3$0^{\circ}C$. A long dew period on the leaf surface and high temperatures were the main contributing factors for disease development and the greenhouse epidemic. Artificial inoculation of the Korean isolate of C. cassiicola revealed resistance in some Korean cucumber cultivars.