• The Korean Journal of Mycology
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• v.34 no.2
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• pp.73-78
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• 2006

Attempts were made to investigate the physiological and genetic changes when two different shiitake (Lentinula edodes) strains are mixed. Mycelial growth of KFRI 180 strain and KFRI 1 strain were investigated 82 mm and 80 mm, respectively. Concerning the weight loss percentage of medium, KFRI 1 strain decreased 2.4% and KFRI 180 strain 1.6%. Plug-shaped spawn had no-problem to incubate and there were no differences among the ratios of mixture. Also, conditions of plug-shaped spawns were similar, When the isolated mycelia from plugshaped spawns was incubated again, KFRI 1 50%-KFRI 180 50% showed decreased growth of mycelia compared with other treatments. The same results were obtained from test tubes filled with sawdust. When surface of spawn bottles were observed, KFRI 1 50%-KFRI 180 50% showed spots, but other treatments were not different from KFRI 1 and KFRI 180. Test was made to confirm the strains by confrontation culture. The mixture of two strains was proved to be KFRI 1 regardless the ratios of mixture. However, by the RAPD primer analysis, when KFRI 1 was mixed with KFRI 180, KFRI 180 was stronger. Thus, the confrontation line on PDA was different from the bands analysis by primers. Attempts were made whether the fruit-bodies were made at the generating condition of spawn bottles. The results were that KFRI 1 100%, KFRI 1 90%-KFRI 180 10%, KFRI 1 80%-KFRI 180 20%, KFRI 1 50%-KFRI 180 50% treatment showed fruit-body formation. The shape of fruit-body was deformed, but the gill was made normally.

• Research in Plant Disease
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• v.18 no.3
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• pp.194-200
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• 2012

The objective of this research was to select effective fungicides for the control of Fusarium head bight (FHB) of wheat. We tested fourteen commercial fungicides against FHB in the laboratory and under field. Fludioxonil FS, Fludioxonil SC, and Benomyl + Thiram WP highly inhibited the mycelial growth of Fusarium graminearum on the medium while Oxine-copper WP, Thiophanate-methyl WP, and Copper hydroxide WP were not effective against FHB. To verify the disease control in field condition, we selected four fungicides such as Fludioxonil SC, Captan WP, Difenoconazole + propiconazole EC, and Metconazole SC. Their control efficacy on FHB disease severity of wheat was examined after the fungicide treatment twice (30th April and 10th May, 2012) in the two field locations (Iksan and Gimje). With no treatment, FHB severity was 45% and 33.7% in Gimje and Iksan, respectively. FHB disease incidence after fungicide treatment was between 0.3% and 2.2% in Gimje, showing over 95% FHB disease control. FHB disease incidence of fungicide-treated sector in Iksan showed slightly higher than Gimje but the control value of fungicides exhibited 87-90%. No side effect of the chemicals was observed in fungicide treatment. These results showed that four fungicides were effective in the FHB disease control in wheat.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.230-238
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• 1998

This study was conducted to compare the regeneration of the seedlings under different vegetation types and to identify the presence of allelopathy in Abies koreana(Ak) natural forest in Banyabong Peak(elevation, 1715m), of Mt. Chiri. Twenty quadrats($10m{\times}10m$) were placed in May, 1996 to classify vegetation structure using TWINSPAN. Water-soluble extracts from leaves and soil humus of different vegetation types were collected to test their effects on both seed germination of Ak and mycelial growth of ectomycorrhizal fungi. Phenolic compounds from soil humus were quantified using HPLC. Among the four vegetation types, Sasa borealis(Sb) was found in both Ak-Quercus mongolica(Qm) and Ak-Rhododendron schlippenbachii(Rs) communities. Natural seeding of Ak was $230,000{\pm}90,000seeds/ha$ in 1995 and their germination rate was 25% in an ideal laboratory condition. Density of Ak seedlings less than 5cm in height was 52,000/ha in 1996, while that of seedlings taller than 5cm in height was only 4,000/ha. In the case of Ak-Qm community, density of Ak seedlings with Sb understory was only 7% of the density of seedlings with Rs understary, suggesting the inhibitory effect of Sb. The germination rate of Ak seeds was significantly reduced by leaf extracts of Sb, and Rhododendron mucronulatum var. ciliatum(Rm) and Ak. Soil humus extract of Ak-Qm-Sb subcommunity reduced germination of Ak seeds by 81% and also reduced by 19% the respiration of mycelia of ectomycorrhizal fumgus, Lactarius sp. Among the seven phenolic compounds identified from the soil humus, extract, Ak-Qm-Sb subcommunity contained significantly high content of p-hydroxybenzoic acid, vanillic acid, and syringic acid. Particularly, p-hydroxybenzoic acid was present at 4.2ppm in the Sb roots and at 16.5ppm in the Sb humus, suggesting that it could be the primary allelopathic compound in Abies koreana forests with Sasa borealis understory.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.417-422
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• 2010

Cultural characteristics Lecanicillium lecani Btab01 and its insecticidal activity against tobacco whitefly (Bemisia tabaci) were investigated. On potato dextrose agar, tryptic soy agar and SDA+Y media, mycelial growth of L. lecani Btab01 was best at $20{\sim}25^{\circ}C$ and suppressed above $28^{\circ}C$. Both solid culture and liquid culture of L. lecani Btab01 showed high insecticidal activity, 93.9 and 98.3% respectively, against nymph of tobacco whitefly, but there is no significant difference. When culture of L. lecani Btab01 was treated at the concentration of $10^5$, $10^6$, $10^7$ and $10^8$ cfu/ml, their insecticidal activity were 5.8%, 33.8%, 77.3% and 98.5% respectively, and $LT_{50}$ values were 16.1 days, 7.3 days, 5.1 days and 3.5 days respectively. When nymphs were treated by the cultures of L. lecani Btab01 and maintained under saturated condition for zero hour, 24 hours and 168 hours, their control activities were 0%, 20.3% and 100% respectively. Spore germination of L. lecani Btab01 was increased about two times by adding edible oil. When L. lecani Btab01 was treated to control nymph with 0.1% edible oil, it showed high control activity(98.6%) compared to single treatment of L. lecani Btab01 (79.9%).