Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae), is a serious pest of stored products. We assessed the efficacy of combined application of Beauveria bassiana AAD16 and azadirachtin against P. interpunctella under laboratory conditions by using filter paper dipping method. P. interpunctella larvae showed lowest LT50 in combined application of AAD16 and azadirachtin compared to the application of only azadirachtin. The mycosis rate of P. interpunctella larvae was 100% after 14 days of the combined application while AAD16 only application showed 93%. These findings suggest that B. bassiana AAD16 and azadirachtin combined solution can be an effective controlling technique against P. interpunctella larvae.

열대식물인 인도멀구슬나무(Azadirachta indica)는 병해충과 방제와 의학적인 목적으로 오랫동안 이용하였다. 본고에서는 님제의 활성 성분인 아자디라크틴의 해충에 대한 곤충생장조절, 기피, 섭식저해, 산란억제 등 다양한 작용기작과 국내 이용현황에 대하여 고찰하였다. 국내 유 통되는 친환경유기농자재 중에서 님제 제품은 총 57종이었다. 그중 효능효과가 표시된 자재는 7종이었고 평균 아자디라크틴 함량은 0.38%로써 세계적으로 유통되는 평균 함량 2.1%와 비교할 때 약 5.5배 낮았다. 국내에서 님제의 방제효과에서 진딧물은 실험에서 다소 변이는 있었으나 대 부분 90% 이상의 방제효과를 보였다. 꽃매미 약충에 누적살충률은 73~77%를 보였고, 총채벌레에 대한 방제가는 50~72% 범위로 살포효과가 인정되었다. 노린재와 나방류에 대한 방제효과는 대체적으로 낮았다. 본고는 유통되는 님제품의 이해와 실험자료의 해석에 필요한 주요한 정보를 제공해줄 수 있을 것으로 기대된다.

The oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is a major pest of apple, peach, and plum in Korea. As a series of experiment we assessed effect of combined application of an entomopathogenic fungi (Beauveria bassiana ARP-14) and a botanical insecticide (azadirachtin) against male and female of adult G. molesta (<5 days old) in glass scintillation vials. LT50 value of combined application of ARP-14 and azadirachtin (51.9 h) was larger than that of positive control λ-cyhalothrin (34.4 h) in adult female G. molesta. But, adult male G. molesta didn't show any statistical difference between the combined application (34.2 h) and λ-cyhalothrin (44.1). Thus, combined application of ARP-14 and azadirachtin can be an optional management tactic against G. molesta.

Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is an important pest of pome and stone fruits, i.e., apple, peach, and plum. We evaluated single or combined application of an entomopathogenic fungi Beauveria bassiana (Balsamo) Vuillemin. ARP14 (1×108 conidia/mL) and a botanical insecticide of azadirachtin (Azatrol, PBI/Gordon Cooperation) (10 mL/L) against first instar larvae (<5 h old) of G. molesta in glass scintillation vial bioassay. Combined use of B. bassiana ARP-14 and azadirachtin showed higher corrected morality of 100% at 8 h than 71.4% in λ-cyhalothrin used as a positive control.

As a broad-spectrum insecticide azadirachtin may cause acute toxicity and alter behavior of natural enemies. We evaluatedthe toxicity of azadirachtin on two egg parasitoids of Riptortus pedestris (Fabricius) (Hemiptera: Alydidae), Ooencyrtusnezarae Ishii (Hymenoptera: Encyrtidae) and Gryon japonicum (Ashmead) (Hymenoptera: Platygastridae), by pre-treatinghost eggs with five concentrations, i.e., 15, 10, 7.5, 5, and 2.5 mL/L. Azadirachtin significantly reduced parasitism byG. japonicum in 15 and 10 mL/L concentrations than other lower concentrations. Similar effect was also observed inO. nezarae. The parasitism reduction capacity (R) for G. japonicum was 40.8 and 33.1% in 15 and 10 mL/L concentrations,but it was 81.6 and 71.4% in O. nezarae, respectively. Based on the IOBC guideline, azadirachtin can be slightly ormoderately harmful to O. nezarae and slightly harmful or harmless to G. japonicum.

Sweet potato whitefly Bemisia tabaci is a serious pest of various economically important crops. For the control of B. tabaci in an environment-friendly way, we demonstrated the effect of azadirachtin, which is an active conpound of neem oil as an botanical insecticide, on the development of B. tabaci by using an assay of single tomato leaf. Egg hatch rates were 53.6, 50.3% at 5 and 10 ppm, respectively. Adult eclosion rates were 30.0, 22.9% at these doses. We determined the whitefly control efficacies of two application methods of neem-based products by comparing between a direct spray of liquid-type into leaves and a soil treatment of pellet-type. Soil treatment of neem was greatly inhibited adult colonization by 75%. Those plants also inhibited the rates of oviposition and larval development. However, single treatment of foliar spray of neem (5-10 ppm) did not significantly inhibit the initial colonization of adult whiteflies. Furthermore, adult colonization was gradually increased regardless of neem spray.