Soybean aphid, Aphis glycines Matsumura has been identified as a pest of soybean in Korea, Japan, and China. The use of synthetic chemical insecticides is a major option to manage this pest, but the demand for environmental-friendly insecticide is increasing. Entomopathogenic fungus is one of the alternatives which is safe for the environment. In this bioassay, leaf dipping method was used to evaluate Beauveria bassiana (Balsamo) Vuillemin ARP14 and GHA. The mortality of both adults and nymphs was not significantly different between the two fungus strains. However, faster mortality rate in both life stages of aphid was found in ARP14 compared to GHA strain. Also, the mycosis rates of both adults and nymphs were higher in ARP14 than in GHA strain. Our results suggest that B. bassiana ARP14 can be an effective and an environmental-friendly control agent for A. glycines.

최근 벚나무에 벚나무깍지벌레에 의한 피해가 증가하여 친환경적인 방제제로서 곤충병원성 곰팡이인 Beauveria bassiana ARP14를 검증하였다. 경북 안동시 안동대학교 캠퍼스 내 벚나무에서 벚나무깍지벌레의 감염율을 조사하고, 벚나무의 연령을 추정하여 상관관계를 분석하였다. 곤충병원성 곰팡이의 살충력을 확인하 기 위해 약충의 이동성이 가장 활발한 4월 말부터 5월 중순까지 벚나무깍지벌레에 감염된 가지를 채집하여 23°C 의 항온기에 보관하면서 두 가지 곤충병원성 곰팡이(ARP14, AAD16)를 살포하여 살충제(스피로테트라맛 액상 수화제) 처리구와 살충률을 비교하였다. 그 결과 대조구(물처리)보다 곤충병원성 곰팡이를 살포한 가지에서 약충의 개체 수가 더 감소하였으나, 살충제를 처리한 가지에서 보다는 약충의 수가 많았다. 따라서 가로수로 많이 식재된 벚나무 해충 방제시 일어날 수 있는 사람에 대한 피해를 최소화할 수 있는 친환경 방제제로서 곤충병 원성 곰팡이를 사용할 수 있을 것이다.

The choice of suitable companion plants is crucial for enhancing pest management strategies in agricultural fields. Riptortus pedestris, an important agricultural pest, has drawn attention for its serious damage on soybean. To identify an ideal companion plant for soybean, we investigated the pest’s behavioral patterns when exposed to corn seedlings in laboratory. Series of choice experiments were conducted for 4th instar nymphs and unmated female adults of R. pedestris when presented with corn and/or soybean pot against soybean or blank pot. In 4th instar nymphs, 56% preferred the treatment of corn pot plus soybean pot over soybean alone pot while 69% of unmated female adults preferred the same combination. These findings provide valuable insights into the behavior of this insect pest, which could be beneficial for establishing polycultures in agricultural fields.

Tetranychus kanzawai Kishida (Acari: Tetranychidae) is a major pest on strawberry, reducing both the quality and quantity of fruit production. We compared the virulence of an entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin ARP14 with a commercial GHA strain against T. kanzawai. In the laboratory, leaf dipping method was conducted while a one-time spray was carried out on selected planting units in strawberry greenhouse with each fungus strain and Triton X-100 as control. Adult T. kanzawai showed lower LT50 when treated with ARP14 strain compared to GHA in the laboratory. The densities of both adult and nymph mites in the greenhouse were significantly reduced in the treatment of two fungus strains compared to the control. The mycosis rate of T. kanzawai in greenhouse was 97.9% at 14 days when treated with ARP14 strain while it was 85.5% when treated with GHA strain. The results suggest that B. bassiana ARP14 can be an effective mycoinsecticide against T. kanzawai.

The ladybird beetles have been used as biological control agents against several pest species. The aim of this study is to evaluate the compatibility between ladybird beetles and an entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin AAD16. The virulence of AAD16 strain was compared with that of commercial GHA strain on three developmental stages of two coccinellids; Harmonia axyridis Pallas and Chilocorus stigma Say. The topical application method was used for both adult and larval stage while dipping method was used for egg stage. The LT50 and mycosis rate for all life stages of two ladybird beetles tested were not significant between AAD16 and GHA strain. In larval stage, the mycosis rates of H. axyridis and C. stigma were 36 and 40% and 63 and 60% in AAD16 and GHA strain. In adult stage, the mycosis rates of H. axyridis (male and female) and C. stigma (unsexed) were 20, 23, and 23% and 26, 30, and 30% in AAD16 and GHA strain, respectively. Therefore, the two predatory coccinellids could be compatible with these two fungus strains due to their relatively lower mycosis rate.