A species of Beauveria bassiana is widely used for biological pest management in many countries. Many efforts have been given to figure out the clear fungal mode of action to enhance the insecticidal activity. Homologous recombination (knock-out) or hairpin RNA (knock-down) is popularly used in fungal gene function study, but gene cloning and generation of knock-out or -down mutants takes long time or temporarily knock-downed. Here in this work, we used previously generated egfp-expressing B. bassiana strain (Bb-egfp #3) and integrated dsegfp to the Bb-egfp #3 using a protoplast integration method. This work suggests that protoplast integration with dsRNA possibly generate significantly reduced gene expression in B. bassiana and the reduction is quite stable over generations which provide easy of functional study for fungal mode of action.

This paper examines a simple one-step and catalyst-free method for synthesizing carbon nanoparticles from aliphatic alcohols and n-hexane with linear molecule formations by using a stable solution plasma process with a bipolar pulse and an external resistor. When the external resistor is adopted, it is observed that the current spikes are dramatically decreased, which induced production of a more stable discharge. Six aliphatic linear alcohols (methanol- hexanol) containing carbon with oxygen sources are studied as possible precursors for the massive production of carbon nanoparticles. Additional study is also carried out with the use of n-hexane containing many carbons without an oxygen source in order to enhance the formation of carbon nanoparticles and to eliminate unwanted oxygen effects. The obtained carbon nanoparticles are characterized with field emission-scanning electron microscopy, energy dispersive X-ray spectroscopy, and Raman spectroscopy. The results show that with increasing carbon ratios in alcohol content, the synthesis rate of carbon nanoparticles is increased, whereas the size of the carbon nanoparticles is decreased. Moreover, the degree of graphitization of the carbon nanoparticles synthesized from 1-hexanol and n-hexane with a high carbon (C)/oxygen (O) ratio and low or no oxygen is observed to be greater than that of the carbon nanoparticles synthesized from the corresponding materials with a low C/O ratio.

Polyphenol profiles, physicochemical properties, antioxidant activities, and inhibitory effect of adipocyte differentiation of Houttuynia cordata fermented with Lactobacillus brevis B84 were evaluated. Six polyphenols were characterized for this plant by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and the results were compared with total phenolic content by a spectrophotometric method. The total amount of the identified polyphenols was lower than that determined by the spectrophotometric method. However, the fermentation process influenced polyphenol composition such as content of vanillic acid and caffeic acid. The phytochemical profiles were evaluated by high-performance liquid chromatography with UV and electrospray ionization mass spectrometry detection (HPLC-DAD-ESI-MSn). Total sugar and reducing sugar contents decreased after fermentation. Antioxidant activities such as DPPH, ABTS, and superoxide anion radical scavenging and reducing power were evaluated to compare the beneficial effect after fermentation. Fermented H. cordata increased the lipolytic effect in 3T3-L1 adipocytes. Overall, the results indicate that the fermentation of H. cordata with L. brevis B84 produces changes of phenolic compounds, antioxidant activity, and lipolytic effect.

The physical and chemical properties of corrugated cardboard-based media were evaluated to assess their suitability as substrates for plants. Samples were collected periodically from the same study area over 5 months to determine any seasonal variabilities. In addition to the corrugated cardboard-based media, the rural soil of the study area was used as the control. The corrugated cardboard-based media showed adequate levels of moisture content and bulk density and correspondingly high porosity values when compared with the rural soil. All corrugated cardboard-based media showed adequate levels of electrical conductivity, organic matter, and correspondingly high cation exchange capacity values when compared with the rural soil in all seasons. The C/N ratio of the corrugated cardboard-based media was similar to the optimal values of 15-20. However, the pH values of the corrugated cardboard-based media were lower than the optimum value(pH 4) for plant growth and rural soil. The moisture content value which cycle bobs up and down according to sampling date, and this means that the moisture content is affected by seasonal changes in the components entering the study area. The corrugated cardboard-based media appear to be acceptable for growing plants(Lotus corniculatus var. japonicus). Finally, the use of this media permits better vegetation establishment than the use of rural soil. Our results prove that corrugated cardboard-based media can exhibit higher plant cover over a long period(September-November) as opposed to rural soil. Our study demonstrates the effectiveness of corrugated cardboard-based media for plant growth, and we recommend that future studies should focus on potential materials relevant to revegetation and management.

Insect-killing fungi have high potential in pest management. A deeper insight into the fungal genes at the whole genome level is necessary to understand the inter-species or intra-species genetic diversity of fungal genes, and to select excellent isolates. In this work, we conducted a whole genome sequencing of Beauveria bassiana (Bb) JEF-007 and characterized pathogenesis-related features and compared with other isolates including Bb ARSEF2860. A large number of Bb JEF-007 genes showed high identity with Bb ARSEF2860, but some genes showed moderate or low identity. The two Bb isolates showed a significant difference in vegetative growth, antibiotic-susceptibility, and virulence against Tenebrio molitor larvae. When highly identical genes between the two Bb isolates were subjected to real-time PCR, their transcription levels were different, particularly in heat shock protein 30 (hsp30) gene which is related to conidial thermotolerance. In several B. bassiana isolates, chitinases and trypsin-like protease genes involved in pathogenesis were highly conserved, but other genes showed noticeable sequence variation within the same species. Given the transcriptional and genetic diversity in B. bassiana, a selection of virulent isolates with industrial advantages is a pre-requisite, and this genetic approach could support the development of excellent biopesticides with intellectual property protection.

붉은불개미는 세계 100대 침입외래 해충 중의 하나로 우리나라에서는 관리 해충으로 1996년도에 지정되었다. 2017년 9월28일 부산항 감만 부두에서 국내 최초로 발견된 후, 2018년에 부산항, 평택항 과 인천항에서 발견이 되었고, 9월18일에 대구의 아파트 공사장에서 내륙에서는 처음으로 발견이 되었다. 대구에서 발견된 붉은불개미도 아파트 건설을 위하여 중국에서 수입한 석재에 혼합되어 수입된 토양과 식물체와 같이 혼입된 것으로 추측이 된다. 그러므로, 현재까지 국내에서 붉은불개미가 번식을 하여 토착화되었다는 증거는 없다. 현재까지 붉은불개미에 대한 종 판명은 전문가에 의한 형태적인 분류가 대부분이다. 그래서, 붉은불개미에 대한 확증을 위해서는 채집된 개체를 검역기관으로 이송하여 분자진단을 실시해야 하므로, 최소 이틀의 시간이 필요하다. 현재 항원항체 반응을 이용한 붉은불개미 진단 키트가 해외에서 개발되어 판매되고 있지만, 낮은 민감도로 최소 3~5개의 충체가 필요한 실정이다. 현재 판매되고 있는 진단키트가 가지는 문제점은 이를 대신할 새로운 키트의 개발이 필요함을 보여주고 있다. 신속한 붉은불개미의 검역현장에서 진단을 가능하게하기 위한 노력 중의 하나로 우리는 붉은불개미의 복부에서 발현되는 유전체에 대한 연구를 수행하였다. 본 발표에서는 그에 대한 현재까지의 연구 진행과 결과를 설명하도록 하겠다. (본 연구는 농림축산 검역본부의 연구비 지원으로 이루어졌음).

The Asian corn borer, O. furnacalis (Crambidae) and the old world bollworm, H. armigera (Noctuidae) simultaneously cause ear damage in corn in Suwon area. It has been assumed that the second generation of larvae of both insects is responsible for the damage. We, therefore, studied proper spray timing of insecticide in order to reduce the damage. A waxy corn hybrid cultivar, Ilmichal, was sown directly on four plots of a field at April 10, April 20, May 4, and May 18, 2018, respectively. A sodium channel blocker, indoxacarb, was sprayed eight times at 3- or 4-day intervals around the silking stage of corn in each sowing plot. At ear harvest time of each plot, we investigated damaged ratio and length of ear, and the numbers of both insect species. The significantly effective spray timings on reduction of ear damage were the sprays at June 29 and July 2 in the plot sown at April 10, the sprays from July 2 to 13 in the April 20-sown plot, the sprays from July 2 to 19 in the May 4-sown plot, and the sprays at July 19 in the May 18-sown plot, respectively. The damage level was positively related to the insect number. The result indicated that the spray at the silking stage of corn was effective on reduction of ear damage. It was assumed that occurrence time of neonate larvae of the insects at silking stage cause the damage, based on the experimental results using screened pots inoculated with the two species.

Entomopathogenic fungi have been known as promising candidates for biological control of insect pests. Recently, researchers consider the fungal thermotolerance in formulations and field applications. In this study, we investigated the production of thermotolerant Isaria javanica and I.fumosorosea conidia through grain-based solid cultures and exposure to light stress. As results, of the ten grain substrates, Italian millet, rice, perilla seed and sesame, rice, sorghum produced highly thermotolerant conidia in the strains. The two strains were exposed to a light stress and showed enhanced thermal stability compared to control, when exposed to 45°C for 2 hours. This work suggests that heatresistant entomopathogenic fungal conidia can be produced by grainbased solid cultures and exposure to light stress.

Japanese pine sawyer beetle, Monochamus alternatus Hope (Coleoptera: Cerambycidae) is considered as a serious pest in pine trees. To develop an eco-friendly strategy to manage this forest insect, we collected entomopathogenic fungi from Korean soil and assessed their virulence against the adults of the insect in laboratory conditions. As a result, two isolates with conidial suspension (1.0×107conidia/ml), showed 87% and 90% mortality 12 days after fungal treatment, respectively. We assessed the potential of the fungi-derived destruxin and protease as additives to the fungal isolates, and they showed insecticidal activity via feeding and spraying treatments. Finally, we produced fungal conidia in massive solid cultures and formulated wettable powders, and now studying optimal conditions of oil-based formulation with two isolates. Based on these results, we are evaluating the control efficacy of the fungal agents against M. alternatus in field conditions.

This investigates the microstructure and mechanical properties of Al hybrid material prepared by electromagnetic duo-casting to determine the effect of heat treatment. The hybrid material is composed of an Al-Mg-Si alloy, pure Al and the interface between the Al-Mg-Si alloy and pure Al. It is heat-treated at 373, 573 and 773K for 1h and T6 treated (solution treatment at 773K for 1h and aging at 433K for 5h). As the temperature increases, the grain size of the Al-Mg-Si alloy in the hybrid material increases. The grain size of the T6 treated Al-Mg-Si alloy is similar to that of one heat-treated at 773K for 1h. The interface region where the micro-hardness becomes large from the pure Al to the Al-Mg-Si alloy widens with an increasing heat temperature. The hybrid material with a macro-interface parallel to the tensile direction experiences increased tensile strength, 0.2% proof stress and the decreased elongation after T6 heat treatment. On the other hand, in the vertical direction to the tensile direction, there is no great difference with heat treatment. The bending strength of the hybrid material with a long macro-interface to the bending direction is higher than that with a short macro-interface, which is improved by heat treatment. The hybrid material with a long macro-interface to the bending direction is fractured by cracking through the eutectic structure in the Al-Mg-Si alloy. However, in the hybrid material with a short macro-interface, the bending deformation is observed only in the limited pure Al.

The change of phenolic compounds and radical scavenging activity of black soybean flours after germination and roasting treatment were evaluated as a part of the purpose of setting the quality of black soybean flours for each application. The moisture content of roasted black soybean flours decreased significantly according to roasting temperature and time, and the crude ash, protein, and fat contents increased. Water binding capacity of roasted black soybean flours without and with germination increased significantly according to roasting temperature and time, however water solubility index and swelling power decreased. The lightness of roasted black soybean flours was significantly decreased, and the redness and yellowness increased. The phenolic compounds and radical scavenging activity of roasted black soybean flours increase with increasing roasting temperature and time. The total polyphenol contents of roasted black soybean flours without and with germination were 5.43∼7.81 and 4.52∼6.17 mg GAE/g, and total flavonoid contents were 2.90∼3.50 and 2.34∼3.01 mg CE/g, respectively. DPPH radical scavenging activity of roasted black soybean flours without and with germination was 254.98∼415.05 and 171.95∼295.15 mg TE/100 g, and ABTS radical scavenging activity was 459.74∼596.37 and 422.95∼526.85 mg TE/100 g, respectively. As a result, it is necessary to set quality standards for each application considering the quality and antioxidant properties of roasted black soybean flours.

Japanese pine sawyer, Monochamus alternatus Hope (Coleoptera: Cerambycidae) in forest is considered as a serious forest pest in pine trees. In this study, we collected entomopathogenic fungi from soil and assessed their virulence against the adults of the inset using a spray method in laboratory condition. Two entomopathogeinc fungi isolates showed high virulence against the adults. In the concentration of 1.0 × 107conidia/ml, the mortality rate of the adults were 53% and 60%. In semi-field condition, one isolate showed a virulence of 60% against the adult. Consequently, we confirmed the possibility of the fungal isolates in controlling the beetles. In near the future, we will investigate several factors which is possibly related to the control of the forest insect pest using entomopathogenic fungi in field conditions, given the importance of fungal formulation and practical application methods.