• 한국잠사곤충학회지
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• 제42권2호
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• pp.99-103
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• 2000

This study was carried out to investigate incubating characteristics, LTSEM observation, nature of a disease of infected silkworms(bombyx mori), LD$\_$50/, optimum infective condition for mass production and infection percentage(%) on conservation periods. On the V8 media, the colony was 0.5∼2.0cm/8 days in diameter and white or slighty colored with a white fluffy to powdery appearance. The conidia was subglobos in shape, zig-zag appearance, 1-celled, hyaline and 3.2$\times$2.4 ㎛ in size on the average. The conidiophore was irregular grouped, hyaline, rounded or flask-shaped. The LD$\_$50/ values of the 2nd and 4th silkworms were each other 6.6142(Log) in natural temperature and humidity (25$\^{C}$, 65%). On optimum infective condition for mass production, all of preservation time(hr.) postinoculation in 1.0$\times$10$\^$8/ conidia/㎖ was over 97% and only 20 hr in 1.0$\times$10$\^$7/ condia/㎖ was over 90%.

• 생명과학회지
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• 제11권3호
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• pp.242-247
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• 2001

Botrytis cinerea E12 was isolated from the leaves, flowers and fruits of eggplant in the greenhouse in Halrim, Kimhae and Dejeo, Pusan. The leaves infected with the pathogen were appeared initially brown-color, small gray spots at the edge, and finally fall down. The fruit was showed the symptoms of circular or irregular shapes, followed by sunken. When the symptoms were developed, the conidia formed on the surface with gray color. To determine the pathogenicity of B. cinerea E12 against the eggplants, the conidia were suspended with 30% tomato juice, PDB and sterile water, respectively. The result showed that the conidial suspension with 30% tomato juice was highly effective on the pathogenicity as more than 90%. Moreover, the symptoms caused by inoculum were the same as those of wild-type pathogen.

• Mycobiology
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• 제28권1호
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• pp.51-53
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• 2000

The powdery mildew of safflower (Carthamus tinctorius L.) extensively occurred at 1999 at the experimental farm of Kyongsangnam-do Agricultural Research and Extension Services. Both sides of the leaves and the older stems were covered with the fungus, and then the leaves and stems turned yellow. The conidia, conidiophores and perithecia were observed on the leaf lesion. Perithecia were ellipsoidal, $80-117\;{\mu}m$ in diameter. Asci were subglobose and $84{\sim}99{\times}59{\sim}73\;{\mu}m$ in size. Ascospore were ellipsoidal to ovoid, and $15{\sim}34{\times}11{\sim}23\;{\mu}m$ in size. Conidia were ellipsoid to barrel-shaped, $25{\sim}37{\times}11{\sim}22\;{\mu}m$ in size and formed in long chains. The causal organism was identified as Sphaerotheca fuliginea. This is the first report on powdery mildew of safflower caused by Sphaerotheca fuliginea in Korea.

• Mycobiology
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• 제44권1호
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• pp.63-65
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• 2016

Cylindrocarpon destructans causes root rot disease in ginseng and can survive for a long time, producing chlamydospores. We optimized conditions to induce chlamydospore production from the conidia of C. destructans, isolated from Korean ginseng. This will provide the basis for testing the efficacy of control agents targeting these chlamydospores.

• Mycobiology
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• 제42권4호
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• pp.317-321
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• 2014

Fruiting bodies similar to those of the ascomycete fungi Podostroma cornu-damae and Cordyceps militaris were collected from Mt. Seunghak in Busan, Korea on August 21, 2012. The fruiting bodies were cylindrical, with tapered ends and golden red in color. The fruiting bodies contained abundant conidiophores bearing single-celled conidia, but no perithecia or asci. Pure culture of the fungal isolates was obtained through single-spore isolation. Analyses of morphological characteristics, including conidia shape, and phylogenetic traits, using internal transcribed spacer sequences, showed that these isolates belonged to the species Simplicillium lanosoniveum. Although this fungal species is known to be mycoparasitic, the isolates obtained in this study were unable to infect fungi. However, silkworms (Bombyx mori) inoculated with the fungal isolates died during the larval or pupal stages, as has been shown for the strongly entomopathogenic fungus Beauveria bassiana. This study is the first report of the entomopathogenicity of S. lanosoniveum and indicates its potential for use in biological control of insects.

• Mycobiology
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• 제37권2호
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• pp.77-81
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• 2009

This study was conducted to identify the Colletotrichum species causing anthracnose disease of strawberry in Balgladesh and to evaluate in vitro activity of commercial fungicides it. Based on morphological and cultural characteristics, all 22 isolates were identified as Colletotrichum gloeosporioides. They developed white or glittery colonies with grey to dark grey reverse colony colors and they produced cylindrical conidia. The efficacy of five commercial fungicides, Bavistin DF, Dithane M-45, Sulcox 50 WP, Corzim 50 WP and Rovral 50 WP, were tested against the fungus. Bavistin inhibited radial growth completely and was followed in efficacy by Dithane M-45. In Bavistin DF treated media, the fungus did not produce conidia. The percent inhibition of radial growth of the fungus was increased with the increasing concentrations of fungicide.

• 한국식물병리학회지
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• 제14권2호
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• pp.120-124
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• 1998

The conidial germination of Pestaotiopsis theae was occurred in cells attched with pedicels, the inferior cell of conidium. The cells were swollen like a ball, and then germinated in 4 hours under favorable conditions. Generally, it was considered that fifty percent of whole conidia was germinated in the range 6~12 hours. The optimum temperature and pH for conidial germination of P. theae (SP-3) causing leaf blight on sweet persimmon was $25^{\circ}C$ and pH 5, respectively. Conidial germination rate was higher than 90% at 100% relative humidity, but never germinated at a relative humidity lower than 88.5%. Conidial germination was highest at the concentration of 1~4$\times$104 conidia/ml. In case of cultural media, the conidial germination was higher than 90% on PDA, PSA, OME and Leonian agar. There was no relationship between light and conidial germination. It was concluded that the key environmental factors affecting conidial germination of the fungus (SP-3) were temperature and moisture.

• 한국유기농업학회지
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• 제19권spc호
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• pp.279-282
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• 2011

This study was carried out to development the environment-friendly control method of Myzus persicae using Beauveria bassiana and Environment-friendly agricultural materials (EFAM). Germination rate the dried conidia of B. bassiana was 90 percent at $24{\sim}27^{\circ}C$ temperature condition. Mortality of M. persicae was 56.7% at $1{\times}10^7$ cfu/ml conidia concentration. Four EFAM such as Pachungtan, Wangjungwang, Newbiodakill, Muginchon were low toxicity to B. bassiana growth. Among them, Muginchon (derris extract) and Wangjungwang (neem extract) could have synergistic effect to aphid mortality when mixing treat with B. bassiana, which protection value was 99% in 3 days after treat.

• Mycobiology
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• 제47권3호
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• pp.280-291
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• 2019

To explore species diversity of Hypocreaceae, collections from Guangdong, Hubei, and Tibet of China were examined and two new species and a new Chinese record were discovered. Morphological characteristics and DNA sequence analyses of the ITS, LSU, $EF-1{\alpha}$, and RPB2 regions support their placements in Hypocreaceae and the establishments of the new species. Hypomyces hubeiensis sp. nov. is characterized by occurrence on fruitbody of Agaricus sp., concentric rings formed on MEA medium, verticillium-like conidiophores, subulate phialides, rod-shaped to narrowly ellipsoidal conidia, and absence of chlamydospores. Trichoderma subiculoides sp. nov. is distinguished by effuse to confluent rudimentary stromata lacking of a well-developed flank and not changing color in KOH, subcylindrical asci containing eight ascospores that disarticulate into 16 dimorphic part-ascospores, verticillium-like conidiophores, subcylindrical phialides, and subellipsoidal to rod-shaped conidia. Morphological distinctions between the new species and their close relatives are discussed. Hypomyces orthosporus is found for the first time from China.

• Journal of Plant Biology
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• 제6권4호
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• pp.1-4
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• 1963

Using conidia of Neurospora, changes in respiratory activities and the sensitivity to the ultraviolet light of the cells at different growing stages were measured by manometric methods, and the correlation between them was observed. Efficiency in the utilization of various carbon sources, such as, glucose, sucrose, maltose, starch and sodium acetate, in growth and exogenous respiration of N. crassa was also determined. Growth rate of N. crassa was decreased considerably in the medium containing sodium acetate than in the glucose medium and was almost zero in the lactose medium, whereas the utilization of sucrose, maltose and starch was ve교 high, as that of glucose. Respiratory activities of the cells veried considerably depending upon their different growing stages. Actively growing hyphae exhibited the greatest activity in exogenous glucose respiration, followed by germinating and activated conidia in decreasing order. There was no proportional relationship between the dose of ultraviolet light irradiated and its effect on the respiratory activity of the cells, though the more the dose of ultraviolet light, the more the injury. The sensitivity of the cells to ultraviolet light varied with the different respiratory activities of the cells linked to the developmental stages. In general, the more actively growing cells having high respiratory activities exhibited the more serious injury.