• Entomological Research
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• v.48 no.5
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• pp.339-347
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• 2018

Seven different strains of Beauveria bassiana were used in a bioassay on Pieris rapae larvae. The results showed that an B. bassiana strain showed relatively high pathogenicity towards P. rapae larvae. The adjusted mortality rate was 92.86 %, and the infection rate was 85.71 % in 10 days post inoculation. Molecular identification was performed to identify the unknown strain. Internal Transcribed Spacer sequence analysis showed that the polymerase chain reaction amplicon length of the unknown strain of Beauveria sp. was 573 bp, and sequence similarity to the known B. bassiana sequences in the NCBI database was 99 %. The B. bassiana strain was named Bb01. The changes of proteins and PPO of P. rapae larvae infected by B. bassiana Bb01 strain at different times was determined. The activity of PPO increased in 1-6 d and decreased in 7 d again after inoculation. The B. bassiana invaded into the insect body affected the balance of the proteins and PPO.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.368-372
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• 1995

To develop a microbial pesticide for the control of pine gall midges. Thecodiplosis japonensis, entomopathogenc fungi were isolated from 233 soil samples in the damaged region of Thecodiplosis japonenesis, and identified with Beauveria spp. 29 strains and Paecilomyces spp. 2 strains. The morphology of entomopathogenic fungi was observed by scanning electron miroscope. In addition, the toxicity of entomopathogenic fungi was observed by scanning electron microscope. In addition, the toxicity of entomopathogenic fungi isolated from soil samples was determined by bioassay against Thecodiplosis japonensis larvae. The result showed that toxicity of relatively pathogenic strains, Beauveria spp. SFB-168-2 was 82.9%, suggesting that Beauveria spp. SFB-168-2 is effective entomopathogenic fungi for the control of pine gall midges.

• Mycobiology
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• v.40 no.2
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• pp.111-116
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• 2012

Ten strains of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were evaluated to find the most effective strain for optimization studies. The first criterion tested for strain selection was the mortality (> 50%) of Spodoptera litura larvae after inoculation of the fungus for 4 days. Results on several bioassays revealed that B. bassiana BNBCRC showed the most virulence on mortality S. litura larvae (80% mortality). B. bassiana BNBCRC also showed the highest germination rate (72.22%). However, its conidia yield ($7.2{\times}10^8$ conidia/mL) was lower than those of B. bassiana B 14841 ($8.3{\times}10^8$ conidia/mL) and M. anisopliae M6 ($8.2{\times}10^8$ conidia/mL). The highest accumulative radial growth was obtained from the strain B14841 (37.10 mm/day) while the strain BNBCRC showed moderate radial growth (24.40 mm/day). M. anisopliae M6 possessed the highest protease activity (145.00 mU/mL) while M. anisopliae M8 possessed the highest chitinase activity (20.00 mU/mL) during 96~144 hr cultivation. Amongst these criteria, selection based on virulence and germination rate lead to the selection of B. bassiana BNBCRC. B. bassiana B14841 would be selected if based on growth rate while M. anisopliae M6 and M8 possessed the highest enzyme activities.

• Journal of Sericultural and Entomological Science
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• v.44 no.1
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• pp.32-36
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• 2002

Occurrence and characteristics of infectious fungi and physiologically abnormal Paecilomyces tenuipes were examined. These unfavorable fungi are recently known to cause yield loss, decreased quality of products in artificial cultivation farms of P. tenuipes. Total 529 fungal isolates were collected from 22 farms of 7 provinces. These isolates were composed of physiologically abnormal P. tenuipes strains and other infectious fungal strains, which constituted 23.2% and 50.9%, respectively. Physiologically abnormal P. tenuipes strains showed irregular synemata, and absence of local color. They were divided into 4 types or C-l, C-2, C-3 and C-4. Other infectious fungal strains were identified to 5 species, Beauveria bassiana, Fusarium sp., P fumosoroseus, Tricothecium roseum, Aspergillus parasiticus, which were 22.1, 13.8, 7.6, 4.0 and 3.4%, respectively. All of them were hyphomycetous fungi, did not produce synemata, and revealed faster growth rate than that of P. tenuipes.

• Journal of Mushroom
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• v.9 no.2
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• pp.87-89
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• 2011

This study was performed to investigate the antibacterial activities and the minimal inhibitory concentration (MIC) of 6 strains of Beauveria bassiana against mulberry pathogenic bacteria. The antibacterial activities and the MIC were measured using paper disc method and broth dilution method, respectively. The antibacterial activities were found out just B. bassiana J200, and shown at 13 mm from Erwinia rhapontici KACC 10407 and at 17 mm from Pseudomonas syringae KACC 10390 and Xanthomonas campestris KACC 12134. The MIC were all observed at 4.0% from E. rhapontici KACC 10407, P. syringae KACC 10390 and X. campestris KACC 12134. The results suggest that B. bassiana could play a good role for biological control against mulberry pathogenic bacteria.

• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.1-16
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• 2021

The phylogenetic relationships among thirty-two strains (P1~P32; including Cordyceps sp., Paecilomyces sp., Beauveria sp., Aranthomyces sp., Isaria sp. and Himenostilbe sp.) in Miryang region located in the southern part of Korea, were investigated based on internal transcribed spacer (ITS) sequences of ribosomal DNA. A fragment of ITS region was amplified by polymerase chain reaction (PCR) using the specific primer pairs ITS1 and ITS4. After obtained same size of PCR products from various strains, we cloned them into a pGEM-T easy vector to determine their sequences. BLAST analyses of the nucleotide sequence ITS1, 5.8S and ITS2 gene fragments revealed the identity and their phylogenetic relationship. Among 32 strains isolated from Miryang region, Cordyceps militaris was shared 100% sequences with Genbank (AY49191, EU825999, AY491992), while some species are not shared perfectly with reported sequences. For example, strain P17 (P. tenuipes in Ulju-gun Gaji Mountain) has some differences among the other strains of P. tenuipes (Miryang-si Jocheon-eup, Miryang-si Gaji Mountain) and those of gene bank. We conclude that ITS analyses with strains in the suburbs of Miryang in this study can be effectively used as a tool for classification, evaluation and collection of the natural eco-type genetic resources.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.221-227
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• 1996

Four strains of Beauveria bassiana F101, F587, F9 and FJ8, were received from Forestry Research Institute,Seoul. The strain, B. bassiana F101, was the most active in the enzymatic activity and spore production. Whenspores of B. bassiana FlOl were sprayed on the female larva of the black tipped sawfly with various concentrationsof 6 xl 0'~-10s~p ores/ml, insects started to die from 5-7 days, and were covered with mycelia andspores in 24-28 days at 25"C, while the insect did not show visible symptoms even after 50 days at 4'C. Theinsect injected with 5 pl of spore solution (3X l0'~-10s~p oreslml) died within 30-98 and 38-218 hours at25$^{\circ}$C and 4"C, respectively. About 3 days (60 hours) after the injection with a concentration of 3 x lo9 spores1ml, at the point of the insect's death, lots of proteins started to disappear '||'&'||' the hemolymph, fat body and carcaseat 25'C. Esterase activity in the tissues was gone suddenly after that time. Six days after the spray, manyprotein and esterase bands were lost in the hemolymph, but not those in the fat body and carcase. When thefungi growing in the host were exposed in the air, they put energy for spore production, while numerous longand thin mycelia branched out from the host body in the soil.e host body in the soil.

• Mycobiology
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• v.29 no.3
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• pp.121-131
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• 2001

This study was carried out to identify the phylogenetic relationships among several caterpillar fungi by comparing the sequences of internal transcribed spacer regions(ITS1 and ITS2) and 5.8S ribosomal DNA(rDNA) repeat unit. The sequences of ITS1, ITS2, and the 5.8S rDNA from 10 strains of Cordyceps species, 12 strains of Paecilomyces, 3 strains of Beauveria, 2 strains of Metarhizium and 1 strains of Hirsutella were amplified, determined and compared with the previously known Cordyceps species. The sequences of 5.8S rDNA were more conserved in length and variation than those of ITS regions. Although the variable ITS sequences were often ambiguously aligned, the conserved sites could be found. In the phylogenetic tree, the species generally divided into three clusters, supported by their morphology and/or host ranges. The 5.8S rDNA and TTS1 sequences among 10 species of Cordyceps militaris were identical and only one base pair in ITS2 sequence was different. Cordyceps sinensis and Cordyceps ophioglossoides were also clearly different, although they belonged to the same cluster. The Geniank database search of species revealed sister taxa of an entomogenous fungus. Metarhizium was used as an putgroup in all taxa.

• Journal of Life Science
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• v.13 no.4
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• pp.400-411
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• 2003

This study was carried out to identify the phylogenetic relationship and to know the distribution of the entomopathogenic fungi by comparing the DNA sequences of internal transcribed spacer regions (ITS1 and ITS2) and 5.8S ribosomal DNA (rDNA) repeat unit. The entomopathogenic fungi had their specific sequences in ITS1 and 2 regions depending on species. The comparison of the ITS sequences of standard strains indicated that the sequences ITS1 were more variable than those of ITS2. It seems that Paecilomyces tenuipes, Isaria japonicus and P. japonicus are the same species but called as different names because of very similar sequences, and unidentified Paecilomyces sp. KACC 40220 and KACC 40656 showed identical sequences to P. tenuipes. Thirty six strains of the commercial products of entomopathogenic fungi used in this study were divided into four groups by the phylogenetic analysis based on 5.85 rDNA and ITS regions. We found twenty-three strains were P. tenuipes / japonica, eleven strains were C. militaris, and other two strains were Beauveria bassiana and C. multiaxialis, respectively.

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.90-95
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• 1999

For the control of the greenhouse whitefly, Trialeurodes vaporariorum entomopathogenic fungi were isolated from forest soils and infected insects. We selected three strains, which showed high pathogenicity and named as SFB-582(Beauveria sp.), SFP-198(Paecilomyces fumosoroseus) and SFV-1053(Verticillium sp.) respectively. Particularly, at the concentration of $10^{7}$ conidia/ml, P. fumosoroseus SFP-198 had the highest pathogenicity, $91.4{\pm}3.5%$ in laboratory. In glasshouse application, $91.4{\pm}3.5%$ SFP-198 showed high protective values($80{\sim}90%$) regardless of developmental stages, which were similar with that of Verticillium lecanii F-903 already reported. Four kinds of formulations of entomopathogenic fungi were developed, formulation with surfactant Silwet L-77 gave best control of greenhouse whitefly(over 90%). These results suggest that P. fumosoroseus SFP-198 is a promising candidate as a microbial pesticide for the control of T. vaporariorum.