점박이응애(Tetranychus urticae)는 250과 1400여종의 식물에 피해를 주고 있는 해충으로 높은 번식력, 근친 교배, 무성생식, 짧은 수명주기 로 년간 발생회수가 많기 때문에 약제에 대한 저항성이 빠르게 발달하는 종이다. 저항성 기작은 AChE 저해, sodium channel modulator, glutamate gated chloride channels allosteric, mite growth inhibitors, inhibitors of acetyl CoA carboxylase, mitochondrial ATP synthase 저 해, mitochondrial complex I, II, III, 그리고 electron transport 저해 등이 있으며 약제에 따라 작용기작이 다르므로 약제살포 시 확인이 필요하 다. 약제저항성 발달을 평가하는 독성시험방법으로 slide dip, leaf dip, leaf disc, topical application, vial leaf dip, spray potter tower, leaf vial dipping 등이 있으며 최근에는 분자학적 진단법 등도 개발되어 있으나 이들 방법은 해충 종이나 발육상태에 약제에 따라 정확도가 달라지므로 현장 에 가장 맞는 방법을 찾아야 할 것이다. 저항성 점박이응애를 효과적으로 관리하기 위한 방법으로 저항성 위험이 낮은 살응애제(chemical acaricide) 약제 선발, 천적인 칠레이리응애, 사막이리응애를 이용한 생물적 방제, 님, 제충국, 등 식물추출물이나 정유를 활용한 친환경적인 방법 등이 제시되 고 있으며 종합관리를 위한 다양한 요인을 찾아 약제 사용을 줄여 나가야 할 것이다.

The two-spotted spider mite, Tetranychus urticae Koch, is one of the economically important agricultural pests globally, as it attacks a wide range of vegetable and horticultural crops. In this study, we evaluated spatial repellent and oviposition deterrent activities of T.urticae in response to fifteen compounds derived from ester-containing natural products. To evaluate the tests, we used bridge two-choice test and host two-choice test in laboratory conditions. Among the eight compounds showed spatial repellent and oviposition deterrent activities against T. urticae at the 20 mg dose and some compounds had the activities at lower dose. We also conducted two-choice test with a blend and single compounds to determine which showed stronger spatial repellent and oviposition deterrent activities. In host two-choice test, we evaluate repellence between distance of compounds. This study concluded that series compounds from ester-containing natural products have the potential to be used managing T. urticae in the field.

식물에 전기장을 처리하면 식물의 생장속도가 빨라지거나 영양학적으로 긍정적인 변화가 생긴다고 알려져 있다. 최근 음이온 처리 시 식물에 전기장을 처리한 것과 유사한 효과가 나타난다고 보고되었고 본 연구에서는 이러한 음이온을 온실해충인 점박이응애와 목화진딧물에 처리하여 방제효과 여부를 확인하였다. 그 결과 음이 온 처리 시 점박이응애와 목화진딧물에서 살충효과와 기피효과가 나타났다. 또한, 점박이응애 알에서도 음이온 처리가 부화율에 영향을 주는 것을 확인할 수 있었다. 이러한 시험 결과를 바탕으로 온실에서 밀도실험 결과, 700,000 ion/cm3 농도에서 무처리구에 비해 밀도가 감소함을 확인할 수 있었다. 따라서, 본 연구는 음이온 처리 시, 부가적인 효과로 온실해충(점박이응애, 목화진딧물)에 대해 친환경적 방제 가능성을 보여준다.

Major pests of greenhouse strawberry include Tetranychus kanzawai (Acari: Tetranychidae) and Bemisia tabaci (Hemiptera: Aleyrodidae) causing significant damage in both yield and quality. We compared control efficacy of two entomopathogenic fungus strains of Beauveria bassiana, AAD16 and GHA, against T. kanzawai and B. tabaci. Both fungus were applied as a foliar spray targeting the undersides of leaves. In preliminary studies in the laboratory, adult T. kanzawai and B. tabaci showed lower LT50 values when treated with AAD16 strain compared to GHA. In the greenhouse, the densities of the both mites (adult and nymph) and whiteflies (adult) were significantly reduced with the application of the two fungus strains compared to the control. The mycosis rate was 88-94% in T. kanzawai and 48-59% in B. tabaci on collected leaves. These findings suggest that Beauveria bassiana AAD16 can be an effective mycoinsecticide against both T. kanzawai and B. tabaci.

The two-spotted spider mite, Tetranychus urticae Koch, is one of the most important agricultural pests. Therefore, we screened fifteen compounds from natural products for their spatial repellent and oviposition deterrent activities against T. urticae in the laboratory by using two-choice and no-choice tests. In the bridge two-choice test, nine compounds showed the spatial repellent effects on T. urticae at 20 mg dose, resulting in reduced numbers of eggs. Among the nine compounds, at 2 mg dose, two compounds were selected as having more spatial repellent activity than the others. The two compounds also showed spatial repellent and oviposition deterrent effects in the two-choice test from hosts. In the no-choice test from a host, the spatial repellent effects of the two compounds to T. urticae were significantly stronger than that of controls. These results suggest that the findings can be used as potential agents for the prevention and population control of T. urticae in the field.

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.