본 연구는 감귤의 해충인 귤굴나방(Phyllocnistis citrella Stainton) 의 포식 기생자 천적의 종류와 기생률을 조사하기 위하여 수행하였다. 2013～2014 제주 감귤원에서 발견된 귤굴나방 포식 기생자 천적은 좀벌상과에 속한 총 7종을 발견되었다. 그 중 좀벌과에 속한 Sympiesis striatipes가 73%, Quadrastichus sp.가 22%로 우점하였다. 나머지 종은 Neochrysocharis sp., Ageniaspis sp., Pnigalio sp., Holcopelte sp., Trichomalopsis sp. (Pteromalidae) 등이었다. 천적의 평균 기생률은 관행방제 과원에서 10.7%, 무농약 과원에서는 32.2% 이었다.

 ,  , Effect of a new crop protectant ‘Bt-Plus’ on natural enemies was analyzed in this study. Tested natural enemies included two parasitic species of Aphidius colemani and Eretmocerus eremicus, and four predatory species of Harmonia axyridis, Orius laevigatus, Amblyseius swirskii, and Phytoseiulus persimilis. ‘Bt-Plus’ was formulated by combination of three entomopathogenic bacteria (Xenorhabdus nematophila (Xn), Photorhabdus temperata subsp. temperata (Ptt), Bacillus thuringiensis (Bt)) and bacterial metabolite (BM). All three types of ‘Bt-Plus’ showed significantly higher toxicities against fourth instar Plutella xylostella larvae than Bt single treatment. Two types of bacterial mixtures (‘Xn+Bt’ and ‘Ptt+Bt’) showed little toxicity to all natural enemies in both contact and oral feeding assays. However, ‘BM+Bt’ showed significant toxicities especially to two predatory mites of A. swirskii and P. persimilis. The acaricidal effects of different bacterial metabolites were evaluated against two spotted spider mite, Tetranychus urticae. All six BM chemicals showed significant acaricidal effects. The BM mixture used to prepare ‘Bt-Plus’ showed a high acaricidal activity with a median lethal concentration at 218.7 ppm (95% confidence interval: 163.2 - 262.3). These toxic effects of bacterial metabolites were also proved by cytotoxicity test against Sf9 cells. Especially, benzylideneacetone, which was used as a main ingredient of ‘BM+Bt’, showed high cytotoxicity at its low micromolar concentration.