• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1348-1350
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• 2010

Conidia of Beauveria bassiana ARSEF-7060, produced in millet amended with plant oils such as sunflower, corn, or cotton seed oil, were exposed to $45^{\circ}C$ of wet heat for 90 min. Conidia from millet+corn oil medium had the highest thermotolerance [$LT_{50}$ (median survival time): 45.7 min]. The mycotized millet grains were coated with each of the same plant oils as a granular formulation and subjected to $50^{\circ}C$ of dry heat for 8 h. Corn oil coating ($LT_{50}$: 8.68 h) was superior to sunflower and cotton seed oil coatings, suggesting the feasibility of using corn oil to increase conidial thermotolerance.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.506-509
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• 2010

The application of Beauveria bassiana SFB-205 supernatant incorporated with polyoxyethylene-(3)-isotridecyl ether (TDE-3) significantly reduced the population of two species of aphids including cotton aphid, Aphis gossypii, and green peach aphid, Myzus persicae, much higher in cotton aphid, compared with supernatant incorporated with Tween 80, which allows the relationship of aphicidal activity with the degradation of aphid cuticles to be determined. Overall, the degradation of the cuticles induced by the supernatant was more remarkable in conjunction with TDE-3 than Tween 80, and this phenomenon was more observable in cotton aphid through SDS-polyacrylamide gel electrophoresis, revealing high correlation with their aphicidal activities.

• Journal of Sericultural and Entomological Science
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• v.42 no.2
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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%.

• Mycobiology
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• v.38 no.2
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• pp.137-143
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• 2010

The production of conidia of entomopathogenic Beauveria bassiana by solid-state fermentation was studied for the development of a biocontrol agent against aphid Myzus persicae. The optimal conditions for conidia production on polished white rice were 40% moisture content, $25^{\circ}C$ culture temperature, 2-day-old seeding culture grown in 3% corn meal, 2% rice bran, 2% corn steep powder medium, initial conidia concentration of $10^7$ conidia/g in the wet rice, 10% inoculum size, and use of a polyethylene bag as a container. The polyethylene bag containing inoculated rice was hand-shaken every 12 hr during fermentation. Using optimal conditions, the maximum conidia production obtained was 4.05 g conidia/100 g dry rice after 14 days of cultivation, a rate 2.83 times higher than conidia yield of pre-optimization.

• Journal of Microbiology
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• v.35 no.3
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• pp.222-227
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• 1997

DNA fragments homologous to chitin synthase gene were amplified from the genomic DNA of Beauveria brongniartii by PCR using degenerate primers. Cloning and sequencing of the PCR-amplified fragments led to the identification of a gene, designated BbCHSl. Comparison of the deduced amino acid sequence of BbCHSl with those of other Euascomycetes revealed that BbCHSl is a gene for class II chitin synthase. The Blastp search of the deduced amino acid sequence of BbCHSl displayed the highest rate of similarity, 95.8%, with CHS2 of Metarhizium unisopliae. Phylogenetic analysis of the amino acid sequences confirmed the taxonomic and evolutionary position of B. brongniartii, which was previously derived by traditional fungal classification based on morphological features.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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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.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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• pp.96-104
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• 2019

Beauveria bassiana, one of the most common entomopathogenic fungi, has been isolated, pre defined and characterized in-house from soil of tea cultivation area. Experiments have been performed to verify the presence of chitinase as intracellular metabolite and its release as extracellular product rendering the spores with biopesticide activity. Although there are many responsible enzymes for the pest killer action of B. bassiana, binding property of chitinase depending on presence as well as absence of serine supplemented in the media has been studied with respect to the production and kinetics. A programmed investigation conclusively indicates that the isolated spore (hyphae) of B. bassiana has been metabolically enriched with the enzyme chitinase in presence of an externally added amino acid serine with its inhibitory kinetics.

• International Journal of Industrial Entomology and Biomaterials
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• v.41 no.2
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• pp.28-35
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• 2020

Entomopathogenic Beauveria bassiana and Metarhizium anisopliae are well-known biological control agents worldwide, and have high potential in industrialization. However, their thermo-susceptibility limits long-term storage under high temperature conditions and insecticidal activity after application in target pests. The virulences of M. anisopliae JEF-003 and JEF-004, and B. bassiana JEF-006 and JEF-007 against bean bug (Riptortus pedestris), and the thermotolerance of conidia produced on three kinds of grains, sorghum, millet and Italian millet as substrates for solid cultures were investigated. Of the three grains, Italian millet was the suitable grains in the production of thermotolerant conidia, and a significant relationship between conidial thermotolerance and the media was demonstrated. This work suggests that biological characteristics of entomopathogenic fungi are altered by culture media, and these results will be a chance to understand the factors in the media which make such changes.

• The Korean Journal of Mycology
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• v.41 no.4
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• pp.295-300
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• 2013

This study was conducted to test effect of fungicides on the spore germination and mycelial growth of BotaniGard$^{(R)}$(Beauveria bassiana GHA). Eight fungicides, which are using for plant disease control in cucumber cultivation, with different concentration were mixed with conidia of GHA isolate for 0.5, 2, and 4 hours. The fungicides trifluminazol, fenarimol, ethaboxam, copper hydroxide and tetraconazol did significantly not inhibit on spore germination and mycelial growth. The trifluminazol, propineb and tetraconazol on high concentrations inhibited the mycelial growth of GHA. However, mixing time of fungicide with conidia of GHA did not affect in spore germination and mycelial growth. These results suggest that fungicide effect needed be checked before mycopesticide is applied in the field.

• Korean journal of applied entomology
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• v.49 no.1
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• pp.43-47
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• 2010

This study was conducted to investigate optimal conditions for formation of synnemata from Beauveria bassiana. The strain of B. bassiana was isolated from a host of Oncotympana fuscata in Halla mountain of Jeju island. The yield of synnemata was the highest at application of brown rice (90%) and silkworm pupae (10%) media. On the other hand, the other media did not result in formation of synnemata. The highest formation of synnemata was achieved at conditions of moderate air inflow and $20^{\circ}C$. The optimal moisture and light intensity for formation of synnemata were 60% and 300 lux, respectively. In addition, inoculation of the liquid spawn resulted in higher yield than that of asexual spore.