Metarhizium은 대표적인 곤충병원성 진균 중 하나로, 종에 따라 매우 다양한 곤충에게 병원성을 일으키는 폭 넓은 기주범위를 형성한다. 이들이 주로 생성하는 것으로 알려진 destruxins (DTXs)이라는 2차 대사산물은 살충 활성 뿐만 아니라 항바이러스, 항증식, 항암 등 다양한 분야에서 효능이 연구되고 있어, 해당 물질에 대한 관심이 집중되고 있다. 살충 물질로서의 DTXs는 여러 곤충에 있어 병원성을 나타내는 것이 확인되었으나, 해충 으로서 전 세계적으로 심각한 경제적 피해를 일으킴과 동시에, 화학 살충제 저항성 문제가 야기되고 있는 목화진 딧물에 대해서는 아직 DTXs의 역할이 연구되지 않고 있는 실정이다. 본 연구에서는 목화진딧물에 대해 곤충병원 성 진균 Metarhizium spp.의 병원성 발현에 DTXs가 미치는 역할을 간접적으로 확인하기 위해, qPCR을 활용하여 진균 처리 후 목화진딧물 사망 시간과 관련하여 충체 내 DTX 합성효소의 발현을 비교 분석하였다.
마이코바이러스는 곰팡이를 감염시키는 바이러스로 자낭균류, 담자균류 및 난균류에서 주로 발견되며 일부 의 경우 곰팡이의 표현형에 영향을 끼치는 것으로 알려져 있다. 이번 연구에서는 대한민국 토양 샘플에서 분리된 65개의 자낭균류 및 접합균류 균주의 전체 핵산을 추출하고, 전기영동을 통해 바이러스 특이적 밴드를 스크리닝 하였다. 스크리닝 결과 65개의 균주 중에서 Tolypocladium spp. 균주 2개와 Marquandomyces marquandii 균주 1개에서 바이러스 특이적 밴드를 발견하였다. 그 후, Cellulose Chromatography를 이용하여 double-stranded RNA 를 분리하고 DNase I 및 S1 Nuclease 처리를 통해 DNA와 single-stranded RNA를 제거하여, Tolypocladium sp. 균주 1개와 Marquandomyces marquandii 균주에서 발견한 특이적 밴드가 dsRNA임을 확인하였다. 추후 virus-free isogenic line을 확보하여 virus 유무에 따른 표현형 변화를 확인하고, 마이코바이러스와 곰팡이 간의 상호작용에 관해 연구할 계획이다.
Aphids are well-known insect pests that, due to their feeding habits, affect various crops' productivity and marketability. Additionally, they cause significant damage worldwide as vectors of viruses. Chemical pesticides are widely used to control these agricultural pests. However, due to resistance to various chemical pesticides, pest control is becoming difficult in agricultural environments. Entomopathogenic fungi such as the genus Metarhizium and Beauveria are being extensively researched as alternatives to these chemical pesticides. In this study, the mycological properties of isolated from soil Metarhizium pemphigi IPBL-H and the insecticidal activity of this strain against Myzus persicae and Aphis gossypii were evaluated for potential of development as a biopesticide.
Background : This study was conducted to examine the suitability of the blue/white vinyl for ginseng cultivation greenhouses in different regions in an effort to develop a stable ginseng cultivation technology and contribute to popularizing ginseng greenhouse farming. Methods and Results : For comparison purposes, ginseng plants were cultivated in the traditional shading and greenhouse shading facilities. The average temperature in the greenhouse shading facilities during the period of May through October was 20.5℃ in Namwon, 21.4℃ in Jinan, and 23.3℃ in Iksan, with Iksan recording a 1.9–2.8℃ higher average temperature, presumably due to its location in a plain area with low elevation. The average temperatures in the traditional shading facilities ranged between 22.9℃ and 25.7℃, 2.4–2.6℃ higher compared with the greenhouse shading facilities. As for the incidence of disease and pest, as low as 0.1–0.3% of the plants grown under greenhouse shading were infected with Colletotrichum dematium, Alternaria panax, and Rhizoctonia solani, whereas much higher incidences were noted in the control plants, with 3.3–11.3%, 4.7–17.0%, 0.1–0.5%, and 3.0–5.7% infected with Colletotrichum dematium, Alternaria panax, Rhizoctonia solani, and Phytophthora cactorum, respectively, throughout the regions. Heat injury occurred only in Iksan (0.3%) in the case of greenhouse-shaded plants, whereas the control plants suffered from much severer heat injury: 3.5% in Namwon, 10% in Jinan, and as high as 35.3% in Iksan. As for the roots, Namwon outperformed other regions in root length (29.7 ㎝), taproot length (8.7 ㎝), and taproot diameter (25.3 ㎜), and also the root fresh weight (53.4 g), followed by Jinan (48.7 g) and Iksan (40.4 g). In yield as well, the greenhouse in Namwon outperformed other regions with 1,297㎏/10a, followed by Jinan (1,183 ㎏) and Iksan (932 ㎏). The effect of greenhouse blue-white vinyl shading on yield by region was analyzed to increase of 177% in Namwon, 209% in Jinan, and 173% in Iksan with respect to their respective traditional shading facilities. Conclusion : The suitability of the blue/white vinyl shading in ginseng cultivation greenhouses was tested experimentally in three different regions. As a result, greenhouse-shaded ginseng plants were found to be much less affected by heat injury compared with traditionally shaded ginseng plants, resulting in much higher yields in all regions. This allows the conclusion that greenhouse ginseng cultivation can contribute to more stable ginseng yield and popularization of ginseng cultivation.