• Korean journal of applied entomology
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• v.52 no.2
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• pp.109-113
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• 2013

A greenhouse soil infested with an obligate nematode parasitic bacterium, Pasteuria penetrans, was used to test the effect of temperatures on the endospore attachment to root-knot nematode, Meloidogyne arenaria, juveniles (J2). Freshly hatched J2s were inoculated to the soil in petri dish and incubated under different temperatures of $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$ for 7 days. The endospore attachment rates were 100% in all the temperatures, while the number of endospores attached per J2 was highest in $25^{\circ}C$ with 28.3 endospores/J2 followed by 20.2, 18.6, and 13.6 in $30^{\circ}C$, $20^{\circ}C$, and $35^{\circ}C$, respectively. When the soil was pre-treated under different temperatures before the J2 inoculation, the endospore attachment rates significantly decreased from 60% in room temperature to $25^{\circ}C$, 31.7, 8.3, 5.0, and 0% after the soil incubation in $-30^{\circ}C$, $4^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$, and $100^{\circ}C$ for 10 days, respectively. The endospore numbers attached per J2 were 3.5, 4.3, 1, 1, and 0 when the soil was pre-treated in $-30^{\circ}C$, $4^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$, and $100^{\circ}C$, respectively, which were lower than 5.3/J2 of room temperature treated soil. The P. penetrans isolate in the soil showed nematode species-specific endospore attachment characteristics with 100% attachment rate only on M. arenaria J2s while the rates were 0% on M. hapla and M. incognita J2s.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.2
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• pp.169-175
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• 2007

The Bio Best Bacillus(B3) and Rotating Activated Bacillus Contactor(RABC) processes, in which Bacillus strains are predominating, are reported to remove nitrogen and phosphorus as well as organic matter effectively. Nevertheless the nutrient removal characteristics of the Bacillus strains have not been studied in detail so far. This study investigated the organic and nutrient removal by Bacillus strains, Bacillus megaterium(KCTC 3007), Paenibacillus polymyxa(KCTC 3627), and Bacillus sp. A12, C21, F12, and L1(isolated from a B3 process), by incubating the strains in 0.2% nutrient broth at $30^{\circ}C$. Burkholderia cepacia(KCTC 2966), a common activated sludge organism, was used as a reference species for comparison. Although the degradation rate was affected by the population sire, the specific removal rates of organic matter by Bacillus strains were greater by $2\sim5$ times than that of Burkholderia. In particular, the culture bottles inoculated with the endospores of Bacillus megaterium and Bacillus sp. C21, F12, and N12 showed significantly higher degradation rate than those of vegetative cells.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.172-183
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• 1994

The productions of arbuscular mycorrhizal fungal(AMF) spores were observed by adding three different commercial fertilizers on AMF inhabiting soils. Various morphological features, vesicles, arbuscles, sporulations of spore, and flower-like-structures, were also found in the mycorrhizal roots during 80 days after transplanting. Spore prodcutions of the employed AMF were observed to be periodically increased with the intervals of 40 days. Sorghum, green onion, hot pepper, and wild legume plants were appeared to be a good plant for productions of AMF and as the host of AMF. The productions of AMF spores was inversely related to phosphate fertilizer, and also observed to be low in the plant pots added with whole balanced fertilizers.

• The Korean Journal of Mycology
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• v.20 no.2
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• pp.134-143
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• 1992

The association of soil environments and sporulation of arbuscular mycorrhizae was investigated using pot cultures. Increased arbuscular mycorrhizal spores as well as the better growth of the host plants were observed when sorghum (Sorghum bicolor) was treated with different soil conditions using several fertilizers with different concentrations. For to five fold increase of sporulation of arbuscular mycorrhizae was noticed depending on the mycorrhizal species. Although there were some differences between the four arbuscular mycorrhizae species and the conditions of soil environments, maximum populations of spores were reached at about 30-40 days after cultivation. The populations of four arbuscular mycorrhizal species was individually fluctuated. Also, the growth rate of host plants were different from the fertilizers over 2-3 times, but the increase of spores were not influenced by it.

• The Korean Journal of Mycology
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• v.21 no.1
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• pp.38-50
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• 1993

Four plant (Sorghum bicolor, Cassia mimosoides var. nomame, Sesamum indicum and Glycine soja) were cultivated at the pots including the soils containing arbuscular mycorrhizal fungi and were also investigated with the colonizations and productions of arbuscular mycorrhizal fungi. Whereas the colonizations of arbuscular mycorrhizal fungi continuosly increased on the roots until 50 days, the productions of arbuscular mycorrhizal fungal spores were fluctuated with the terms of 30 days after inoculated. This indicated that the colonizations on the roots were not correlated with productions of arbuscular mycorrhizal fungal spores. Also, the various soils collected were applied to this technique by using pot cultures. Out of 82 various soils collected, the spore productions of arbuscular mycorrhiaze were observed only from 42 soils. The spores cultured under artificial conditions were identified to 15 species with four genera. The spore productions of arbuscular mycorrhizal fungi using this technique would be considered to be related to the soil pH: The spore productions were found in the low pH for the species of Acaulospora and Glomus, the those near pH 7.6 for the species of some Glomus, Scutellospora and Gigaspora.

• The Korean Journal of Mycology
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• v.19 no.3
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• pp.186-202
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• 1991

Out of the 36 species (22 families) of horticultural plants collected from the horticultural shop around Cheong Ju, the 17 plant species (47.2%) were infected with VA-mycorrhizae in the root tissues. Also, the chlamydospores or azygospores of VA-mycorrhizae were identified (two genera, three species); Acaulospora spinosa, Glomus etinucatum, and G. tortusom. VA-mycorhizae found from the cultivated plants around Korea National University of Education and other area were also identified (four genera, six species); A. myriocarpa, Gigaspora decipiens, G. caledonium, G. glomerulatum, G. microcarpum, and Scutellospora calospora.

• The Korean Journal of Mycology
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• v.20 no.2
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• pp.126-133
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• 1992

Using the soils containing several arbuscular mycorrhizae, the degrees of infection on the plant roots were measured with the different level of phosphate added on pot cultures. Infection on the plant roots was independent of the phosphate level for the roots of sorghum, but formation of arbuscular mycorrhizae in the roots was inversely related to the growth of soybean roots. It was concluded that infection of arbuscular mycorrhizae would be related to the phosphate level in the soils. Plants, themselves, were considered to control the infection of arbuscular mycorrhizae under the environments of soils, especially amount of phosphate.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.437-441
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• 2005

This study was investigated to compare the suppression of Meloidogyne arenaria by different treatments of Pasteuria penetrans which is known for biological control agent against Meloidogyne spp.. In order to select proper number of P. penetrans showing good suppression effect, P. penetrans were mixed with M, arenaria for attachment using three different concentration such as $3{\times}10^4$, $3{\times}10^5$ and $3{\times}10^6$ endospores/5 g medium, followed by treating them onto the roots of tomato. After 14 weeks incubation, P. penetrans at $3{\times}10^6$ endospores showed highest activity against the formation of gall caused by M, arenaria. At a dose of $3{\times}10^5$ endospores/5 g medium, P. penetrans was treated into soil either mixing with soil or spray onto soil surface for comparing of suppressive efficacy. When the antagonistic bacterium was treated by the former method, it suppressed more effectively Using P. penetrans at $3{\times}10^6$ endospores and mixing with soil method, suppression was compared among P. penetrans, $PASTORIA^{(R)}$(Japan) and $Fosthiazate^{(R)}$(Korea). P. penetrans was more potent than $PASTORIA^{(R)}$(Japan) and as similar as $Fosthiazate^{(R)}$(Korea). Therefore, these results suggested that P. penetrans can be used for controling of M. arenaria as biological control agent. Furthermore, thess results can be provided to develop environmentally-friendly nematicide.

• Journal of Veterinary Clinics
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• v.14 no.2
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• pp.349-351
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• 1997

7세의 홀스타인 암소에서 엽록소가 없는 Prototheca에 의한 만성적인 진행성 유방 염의 발생에 대해 보고한다. 유방염 우유로 만든 습윤표본에서 명확한 세포벽과 내생포자를 갖고 있는 구형 내지 난원형의 병원체가 직접 관찰되었고, Sabouraud배지에서의 순수배양물 에 대해 Wright염색 및 PHOL염색을 했을 때 algae가 증명되었으며, nutrient배지에서 세균 이 중식하지 않아서 Prototheca가 유방염의 원인으로 제시되었다. 이 병원체는 자연상태에서 는 사물기생성이지만 감염원은 확실하지 않았다. algae와 진균의 형태학적인 연구를 하는데 있어서 PHOL염색액을 광범위하게 응용할 수 있음을 제시하였다. Prototheca의 ecology와 병원성을 규명하기 위해 더 많은 연구가 이루어져야 될 것으로 생각된다.

• The Korean Journal of Mycology
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• v.20 no.2
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• pp.85-94
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• 1992

Five sporocarpic species of Glomus were found at the four sites of the different plant's cultivations in Korea ; G. clavisporum, G. liquidambaris, G. rubiforme, G. sinuosum, and G. taiwanense. The morphological characteristics of these species collected were observed and compared under light microscopes. Three species G. clavisporum, G. liquidambaris and G. taiwanense were similar with each other in the aspects of having no peridium and the clavate spores orderly arranged within sporocarps. G. sinuosum was different from the other in the aspects of having a thick and sinuous peridium and the orderly arranged spores within sporocarps. However G. rubtforme was different from the other four species in aspects of sporocarps haying ovoid spores arranged irregulary.