감자, 가지등 가지과 작물을 가해하는 해충인 큰 28점박이 무당벌레를 1983년 1986년까지, 매년 6월부터 9월까지 채집하였고, 이들을 공격하는 기생천적의 종류, 각 기생천적에 따른 기주곤충의 령기별, 월별 기샐률이 조사되었다. Nothoser plus afissae (Watanabe), (벌목:Proctotrupidae), Uga menoni(Kerich)(벌목:수중다리 좀벌과), Pedipbius foveolatus (Crawford), (벌목:좀벌과) 등 3종류의 기생천적이 큰 28점박이 무당벌레를 공격하는 것으로 조사되었다. N. afissae는 2령~4령때 채집한 유충에 기생하는 것으로 조사되었으며, 특히 3령때 채집한 기주에서 가장 높은 기생률로 나타났으며, 유충때, 기생해서 번데기때 우화하는 U.mononi의 경우 3령-번데기때 채집한 기주에 기생된 것으로 조사되었고, 번데기 때 재칩한 기주에서 높은 기생률을 나타냈다. N.afiss와 U.mononi는 6월뷰터 9월가지 전 조사기간에 걸쳐서 기주를 공격하는 것으로 조사되었으며, N.afissde 는 조사된 다른 기생천저등에 보다 기생률이 월등이 높은 것으로 조사되었으며 U.mononi의 겨우는 7월에만 높은 기생률을 나타냈다. P.foveolatuss는 다른 두 종류의 기생천적과는 달리 다매발생하는 것으로 남부지방에서는 8월초부터 출현하나, 경기도 지역에서는 9월초에 나타나기 시작했으며 기생된 큰28점박이 유충 1개체로 부퍼 평균 13.8개체의 성충이 우화하는 것으로 조사되었다.

본 시험은 수도 멸구류의 난기생봉인 Anagrus nr. flaveolus의 월동후 반휴에 있어서 기생활동시기와 맥전에 있어서 기생율, 기주범위 그리고 본답에 있어서 기생활동등에 관하여 1977년부터 1979년까지 경남 진주에 위치한 본 시험국 시험포장을 중심으로 실시한 것으로서 그 결과를 요약하면 다음과 같다. 1. 반휴에 있어서 Anagrus nr., flaveolus의 월동후 기생활동은 4월상순에 가장 활발 하였으나 4월중 이후는 맥전으로 이동됨에 따라 현저히 감소되었다. 2. 맥전에 있어서 Anagrus nr. flaveolus의 애멸구 (Laodelphax striatellus F.)의 난에 대한 기생율은 애멸구 산란 최성기인 4월 중하순경에 였다. 3. 본답에 있어서 A. nr. flaveolus의 기생범위은 애멸구(Laodelphax striatellus F.), 흰등멸구(Segatella furcifera H.) 및 벼멸구(Nilaparvata lugens S.)였으며 그 중에서 애멸구난에 대한 기생율이 가장 높았다. 4. 본답에 있어서 기생활동은 7월상순과 8월하순9월상순 사이에 가장 활발하였으며 농약을 많이 살포하는 시기인 7월 8월은 살충제 무살포답이 살포답에 비하여 기생율이 현저히 높았으며 10월 이후부터 월동전까지는 반휴에서 기생활동이 활발하였다.

현재 우리나라에서 사용되고 있는 수종의 수도용 살충제들에 대하여 벼멸구와 이의 주요천적인 황산적거미에 대한 상대독성을 실내에서 미량국소 처리방법으로 반치사약량을 조사 비교한 결과 PAP(0.4), MPP (0.7), MEP(1.8), Diazinon(2.8) , Carbofuran(7.5), NAC(11.3), BPMC(17.5), Pyridaphenthion(35.9), MIPC(65.7)의 순이었으며 특히 MIPC, Pyridaphenthion은 벼멸구와 황산적거미에 대해 선택성을 나타내었다.

The differential susceptibility of the two spotted spider mite, Tetranychus urticae and its predator, Phytoseiulus persimilis against extracts of Gleditsia japonica var. koraiensis, Camellia sinensis, Cinnamomum cassia, Lantana camara and their mixtures was evaluated. The plant extracts tested were much less toxic to P. persimilis than to T. urticae. The plant extracts tested had little effect on the survival of P. persimilis adult females. Moreover, reproduction of P. persimilis adult females and eclosion of eggs deposited by treated predators were not seriously affected. The treatments of the plant extracts tested showed no serious toxic effect on P. persimilis eggs and exhibited 84∼100% hatchability. The treatments with mixtures 3 and 1 were effective against the adult females of T. urticae and yielded 76.0% and 72.7% adulticidal activity at 7 days after treatment, respectively. The treatment of mixture 2 revealed 63.3% adulticidal activity. Generally, the acaricidal activity of the individual treatment of each plant extract was lower than the mixtures. The adult females of T. urticae treated with mixtures 3 and 1 produced only 29.5∼31.3% as many eggs as the control females did. All the plant extracts tested exhibited no noticeable toxic effect to the eggs of T. urticae. These results suggest that mixtures 3 and 1 might be used for the control of T. urticae, and expected to be promising candidates for use in integrated mite management program with P. persimilis.

The susceptibility of the predatory mite, Neoseiulus californicus to extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures was evaluated in laboratory bioassays. In treatments with plant extracts tested, 76-86% of adult female predators survived after 7 days after treatment. Adult female predators treated with plant extracts tested produced 68.3-81.1% as many eggs as did control females and eclosion of eggs deposited by treated predators was not affected. Moreover, treatment of plant extracts tested showed no toxic effect on N. californicus eggs and produced 100% hatchability. Survival of N. californicus nymphs was not seriously affected by exposure to the plant extracts tested. Immatures of N. californicus survived on the leaf disc treated with plant extracts tested and 78-90% of immature predators reached adulthood. These results suggest that extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures expected to be promising candidates for use in integrated mite management program with N. californicus.

The susceptibility of the twospotted spider mite, Tetranychus urticae and the predatory mite, Phytoseiulus persimilis to extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures was evaluated in laboratory bioassays. Treatments of mixture 1 and 2 were effective against adult females of T. urticae and yielded 73.3 and 70.7% adulticidal activity at 7 days after treatment, respectively. Treatment of mixture 3 revealed 62.7% adulticidal activity. However, M. azedarach, P. nigrum and S. velutina had lower adulticidal activity than the other treatments. Adult females of T. urticae treated with mixture 1 and 2 produced only 11.1-16.7% as many eggs as control females did. All the plant extracts tested were ineffective to against the eggs of T. urticae. Plant extracts tested had little effect on the survival of P. persimilis adult females. Moreover, reproduction of P. persimilis adult females and eclosion of eggs deposited by treated predators were not seriously affected. Treatment of plant extracts tested showed no toxic effect on P. persimilis eggs and produced 100% hatchability. These results suggest that mixture 1 and 2 might be used for the control of T. urticae, and expected to be promising candidates for use in integrated mite management program with P. persimilis.

This study carried out to evaluate toxicology of Chrysanthemum cinerariaefolium and Melia azedarach against natural enemies in the laboratory, and the diamond backmoth, Plutella xylostella, on chinese cabbage. In the evaluation of the toxicity on predatory mite of phytoseiid Phytoseiulus persimilis, Hypoaspis aculeifer, Amblyseius cucumeris, A. wormersleyi, A. swirskii, the two plant extracts were classified into moderate selective toxicity as recommended by international organization of biocontrol (IOBC). The mummies parasitic natural enemies, Trichogramma evanescens, Aphidius ervi, Aphidius colemani, Eretmocerus eremicus, Encarsia formosa were found to be relatively safe to the plant extracts except Eretemocerus eremicus. In the field study for the control of diamondback moth, Plutella xylostella, single spray of C. cinerariefolium indicated that the control effect dropped from 21th days after the spraying. In the 3 times of spray with 7 says intervals, the mortality effect low at the beginning, but increased to 91.1 at 21 days after spraying. Single spray of M. azedarach showed a 96.7% mortality on P. xylostella at 14 days after spraying, and thereafter decreased. In the three times of spray with 7 days intervals of M. azedarach, the mortality of P. xylostella was 100% at 14 days and its effect was maintained to 28 days after treatment. Consequently, it was suggested that M. azedarach be sprayed before C. cinerariaefolium application.

This experiment was conducted to investigate the effect of plant extracts, Chrysanthimum cinerariefolium and Melia azedarach to natural enemies and management of two spotted spider mite, Tetranychus urticae in organic strawberry fields in Jeonnam area. Plant extracts were highly toxic against Phytoseiulus persimilis, but low against Orius laevigatus. In the residual effect against Phytoseiulus persimilis, C. cinerariefolium showed lower level than M. azedarach which safe at least 1 day after spray. Emergence rates of parasitoids were about 40% at seven days after spray. Eretmocerus eremicus has very low emergence rate in treatment of M. azedarach, so it should release after spray of M. azedarach. To control of T urticae C. cinerariefolium (CC) sprayed first and then sprayed C. cinerariefolium or M. azedarach (MA) for two and three times at a week interval. In the treatment of CC+MA and CC+CC+MA, the density of T urticae was inhibited by 15th day but increased afterward. In CC+MA+CC, that of T urticae inhibit from 8 days but also increased after 15th day. In case of spray M. azedarach (MA) first, the treatment of MA+CC, MA+MA+CC, MA+CC+MA suppressed T urticae from the first day so the densy of T urticae maintained low level to 30 days after spray. It suggested that M. azedarach should spray first and then alternative spray. When C. cinerariefolium sprayed before and behind to release of P. persimilis, the density of P. persimilis maintained unchanged but could not suppress T. urticae after 8 days which T. urticae increase time. When M. azedarach sprayed, the density of T. urticae rapidly decreased. It was accompanied with P persimilis so T. urticae did not occur at 8 days after treatment.