• KSBB Journal
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• v.9 no.1
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• pp.16-25
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• 1994

Sporulation mutants of Bacillus subtilis were developed for overproduction of heterologous proteins. The strains spoOJ spoIIG, and spoOJ spoIIG double mutant were constructed from two pretense-delfted mutant (DB104). The vector containing aprE gene was integrated in the chromosome of each strain, then the morphology of each strain was observed by TEM (trasmission electron microscopy). The morphology of spoOJ mutant and spoIIG mutant coincides with the description of the previous reports, respectively. The sporulating cells of spoOJ SpoIIG double mutation resemble spoIIG mutant more similarly, but with a little rougher cell wall membrane. The spoOJ mutation in B. subtilis gives negative effect on aprE activity with only a decreased sporulation frequency. On the contrary spoIIG mutation increases the aprE activity twice with an undetectable sporulation frequency. In the case of spoOJ and spolIG, i. e. double mutation, the effect of spoOJ on aprE activity seems to be relieved and the double mutant shows more or less the same aprE activity compared to spoIIG mutant.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.320-329
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• 1997

Botrytis cinerea isolates obtained from infected plants of cucumber, tomato, and strawberry were divided into three groups (sporing, sclerotial, and mycelial types). Of which sclerotial types were the major group. There were no correlations between morphological phenotypes and responses to benzimidazole and dicarboximide fungicides. External structure of conidia of three phenotypes by scanning electron microscope was the same with verrucose surface. Mycelial type was the most virulent on fruits of eggplants. Comparative tests were carried out to examine correlations between the virulence and production of fungal enzymes such as phenol oxidases, pectin methyl esterases (PME), amylases, cellulases, ureases, ${\beta}-glucosidases$, and proteinases. There was no correlation among the phenotypes in production of phenol oxidases and ${\beta}-glucosidases$. However, there were significantly different from each other in PME, amylase, cellulase, urease, and protease activity.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.177-184
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• 2009

This study was carried out to investigate infection process, symptoms and main component of the domestic silkworm, Bombyx mori. larvae and pupa infected with the entomopathogenic fungus Cordyceps, Paecillomyces tenuipes. The Cordyceps, Paecillomyces tenuipes, was highly infectious to the silkworms. A pathogenicities of Cordyceps, Paecillomyces tenuipes, may be highly virulent because of the low resistance or high susceptibility of the silkworms. The silkworm larva infected with Cordyceps formed phialospores on the phialides at the imperfect stage of the genus Cordyceps, But silkworm pupa infected with Cordyceps formed ascospores in the asci at the perfection stage of the genus Cordyceps. The results of analysis of health silkworm pupa and silkworm pupa infected with Cordyceps were obtained that amino acid, fatty acid, and nucleoside were very different.

• Journal of Life Science
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• v.12 no.6
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• pp.708-714
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• 2002

A new leaf blight was found on the perilla leaves at the major perilla-cultivating areas such as Kangdong in Busan and Miryang in Kyungnam province. Symptoms of the disease initially appeared on the edge of perilla leaves showing black necrosis and drying, and the infected leaves were finally fell down. The SD1 isolate showing strong pathogenicity and forming abundant conidial spores on the diseased lesions was isolated. Among the tested media, mycelial growth was abundant on PDA (Potato Dextrose Agar) medium at $25^{\circ}C$ under dark condition, but conidial formation was greater on V8A (V-8 juice A8ar) medium than that on PDA medium. Optimal temperatures for mycelial growth and conidial formation on PDA medium were respectively $25^{\circ}C$ and 3$0^{\circ}C$. The rate of conidial germination and the elongation of germ tube were more effective in 10% tomato juice than those in PDB (Potato Dextrose Broth) and sterile water. In 10% tomato juice, the rate of conidial germination and the length of germ tube were 100% after incubation for 24k and 535.2${\mu}{\textrm}{m}$ after incubation for 36hr, respectively. According to the result of pathogenicity, it revealed that conidial suspention with 10% tomato juice was the most effective for pathogenicity test showing as 100% of disease incidence, and the symptoms caused by artificial inoculum were same as those of naturally infected perilla. In this study, the SD1 isolate according to the results of morphological characteristics, the incubation characteristics and pathogenicity was firstly identified A. alternata, and named as leaf blight of perilla.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.71-71
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• 2018

본 연구는 각시톱시네고사리(Dryopteris hangchowensis Ching)의 전엽체 증식 및 포자체 형성을 위한 번식방법을 구명하고자 수행되었다. 각시톱지네고사리의 식물체를 무가온 온실에 재배하면서 포자를 채취하였으며, 수집된 포자는 기내에서 발아시켜 전엽체를 획득한 다음 계대배양하면서 실험의 재료로 사용하였다. 전엽체 대량증식을 위하여 1/4, 1/2, 1배로 조절한 MS배지와 Knop배지를 조성하였다. 이후 전엽체 300mg을 균일하게 다져 조성된 배지에 8주간 배양하였다. 연구의 결과, 전엽체의 생체중은 1/2MS와 1/4MS에서 3.4g으로 가장 많이 증가하였다. 현미경 관찰의 결과, 두 배지 모두 정상적인 전엽체의 형태로 발달하였으며, 생육도 양호하였다. 포자체 형성을 위한 적정 배양토의 혼합조건을 확인하고자 원예상토, 피트모스, 펄라이트 및 마사토의 혼합비율을 5종류로 달리하여 조성하였다. 준비된 배양토를 사각분($7.5{\times}7.5{\times}7.5cm$)에 충진 후 기내 배양한 전엽체 1g과 증류수를 함께 10초간 분쇄하여 토양표면에 균일하게 분주한 다음 12주간 재배하였다. 연구의 결과, 원예상토, 피트모스, 펄라이트를 1:1:1(v:v:v) 비율로 혼합한 토양에서 포트 당 223.7개로 가장 많은 포자체가 형성되었다. 또한 형성된 포자체의 생육을 조사한 결과, 상기 토양에서 생체중, 엽수, 엽장, 엽폭, 근수, 근장 및 SPAD value 등의 생육수치가 우수하였다. 따라서 각시톱시네고사리의 전엽체 증식에 적합한 배지는 경제성과 생육수준을 고려하여 1/4MS 배지가 적합하며, 포자체 대량생산을 위해서는 원예상토, 피트모스, 펄라이트를 1:1:1(v:v:v)로 혼합한 토양이 적합하다고 판단되었다.

• Korean Journal of Organic Agriculture
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• v.19 no.3
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• pp.343-355
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• 2011

This work was studied the effects of spore density and infection of arbuscular mycorrhizal fungi (AMF) for no-tillage organic cultivation of pepper with wintering green manure crops cultivation in greenhouse field. Spore density of arbuscular mycorrhizal fungi (AMF) in green manure crops was 189 spores/30g fresh soils in control including alive spore (82 spores). Spore density of AMF in all green manure crops was totally 196~226 spores/30g fresh soil and alive spore was 84~112 spores/30g fresh soil. Spore density of AMF in soils of Pepper crop was range of 48.0~56.7 spores/30g fresh soils after cultivation of green manure crops. Infection structure of AMF was not significantly difference in soils of green manure crops and Pepper crop after cultivation of green manure crops. Infection rate of AMF in roots of green crops was low level by 2.8% in giant chickweed, 7.4% in rye, 9.3% in hairy vetch. Infection rate of AMF in roots of barley was the highest level by 20.3%. Infection rate of AMF in roots of Pepper crop was range of 5.2~7.2% after cultivation of green manure crops Also, infection rate of AMF in roots of Pepper crop was 8.1% after the harvest of barley. Infection structure of AMF in barley very well consisted of network with internal hyphae, while hairy vetch and rye tended to no network. There was not a significant relationship between spore density in soils and infection rate of AMF in rhizosphere of Pepper.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.360-364
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• 2006

The gametophytes of Cyrtomium falcatum and Cyrtomium caryoptideum var. coreanum arising from spores were mechanically homogenized and cultured In vitro, to study their gametophyte ontogeny and sporophyte development. Homogenized gametophytic tissues formed as one-dimensional filaments after 2 weeks in culture and then glowed into blanched gamatophytes after 4 weeks. After 6 weeks, which were developed to two dimensional plates with apical notch and meristem in central zone. After 8 weeks in culture, apomictic buds were formed on the midribs without archegonium formation and these buds developed to sporophytes after 10 weeks in culture. Flow cytometric analysis of gametophytes and apomictic sporophytes revealed that both forms had the same ploidy level in C. falcatum and C. caryoptideum vu. coreanum, respectively. This is to certify that C. caryoptideum var. coreanum was an apomictic fern as well as C. falcatum.

• Korean Journal of Plant Taxonomy
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• v.36 no.1
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• pp.1-19
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• 2006

Description of spore morphology of Korean Polypodiaceae has on LM and SEM and key to the genera are provided. Korean Polypodiaceae monad, monolete with bilateral symmetry, bipolar and oblete spore except for Loxogramme grammitoides having trilete spore with radial symmetry. In spore wall structure, exopore showed variable patterns enough to distinguish genera. Perispore was found in all the species examined. The patternof perispore and exospore was most similar in all the species examined except Crypsinus, Pyrrosia hastata ans P. linearifolia. The perispores of Crypsinus, Pyrrosia hastata and P. linearifolia were echinate and gemmate, rugulate, and verrucate respectively. In term of exospore wall sculpturing, Polypodium and Loxogramme showed fossulate, Lepisorus, rugulate with irregular verrucate, Crypsinus ans Coloysis showed psilate or rarely verrucate in the latter, Neocheiropteris ensata showed dense small verrucate, Lemmaphyllum microphyllum showed complex reticulate and Pyrrosia showed verrucate or psilate.

• Journal of the Korean earth science society
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• v.29 no.6
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• pp.466-473
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• 2008

This study deals with the morphological characteristics and structure of organ fossils of Neocalamites carrerei such as rhizomes, aerial leafy stems, and cones collected in situ from the Amisan Formation of Nampo Group. Judging from the size of some extant Equisetum and paleoclimate of Daedong flora, it is considered that the size of Neocalamites carrerei was probably very large. The cone of Neocalamites takahashii (Kon'no) is closely associated with the leaves of Neocalamites carrerei. It indicates that two organ fossils mentioned above probably belong to the same species. Comparing with very abundant occurrence of aerial leafy stems and rhizomes in the Amisan Formation, cones are very rare. This fact implies that Neocalamites reproduce not only by spore reproduction, but also by asexual reproduction. Neocalamites largely differ in the leaf form and size from Equisetum.

• Journal of Sericultural and Entomological Science
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• v.38 no.1
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• pp.31-35
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• 1996

To develope a solid culture media for the mass culture of Beauveria bassiana conida, wheat bran was selected as C source and N source. The pellet media were prepared without(P-I) and with(P-II) solidified ingredient. The moisture for the growth of B. bassiana was required over 4 : 2 of Media : D.W (W/V). The growth of Beauveria bassiana on the media type was more effective in media of pellet type than that of powder type. In addition, production of Beauveria bassiana conidia on the media size was more effective in media of S type($\Phi$3mm) than that of L type($\phi$7mm). And the yield of Beauveria bassiana conidia at 2$0^{\circ}C$ cultivation on 3 weeks post inoculation was similar to that of $25^{\circ}C$. Above-mentioned results showed that pellet medium (P-I) was effective to growth of Beauveria, suggesting that the pellet media may be useful in the mass production of Beauveria bassiana conidia.