Penetrations of flupyrazofos against Plutella xylostella(Lepidoptera :Yponomeutidae) and Spodoptera exigua(Lepidoptera : Noctuidae)

배추좀나방과 파밤나방에 대한 flupyrazofos의 체벽 투과량

Tolerance mechanism to flupyrazofos was examined with Plutella xylostella (L.) and Spodoptera exigua by investigating the penetration rate of flupyrazofos into larvae body. On determining effective washing of $^{14}C$-flupyrazofos, the washing volume to recover over 98% of $^{14}C$-flupyrazofos was observed at three times (each time: 1 mL). To select a suitable solvent, the recovery rates of each solvent in 3rd instar larvae of DBM were above 98%, but the washing rates of acetone, hexane and ethyl-acetate were 85.1%, 67.2% and 68.4%, respectively. In the BAW larvae, although the recovery rates of each solvent were above 99%, the washing rates of acetone, hexane and ethyl-acetate were 83.5%, 65.9% and 71.7%, respectively. The $PT_{50}$ values of $^{14}C$-flupyrazofos were 0.731 h (44 min) in the DBM larva and 0.504 h (30 min) in the BAW larva. Radiocarbon in acetone washing (external fraction) decreased more quickly in the BAW larva than in the DBM larva, and amount of radiocarbon in larvae body increased more quickly with time in the DBM larva than in the BAW larva. In contrast, amount of radiocarbon in excreta increased more rapidly with time in the BAW larva than in the DBM larva.

배추좀나방과 파밤나방에 대한 flupyrazofos의 작용기작을 구명하기 위하여 한국화학연구소에서 분양을 받아 실내에서 19세대 누대 사육한 배추좀나방과 포장에서 채집하여 실내에서 인공사료를 이용하여 25세대 누대 사육한 파밤나방을 대상으로 $^{14}C$-flupyrazofos를 처리하여 $^{14}C$-flupyrazofos를 검출하기에 적합한 용매와 두종간의 체벽 투과량을 조사하였다. 배추좀나방과 파밤나방 충체에 있는 $^{14}C$-flupyrazofos의 각 용매별 검출율은 hexane과 ethyl-acetate보다 acetone을 사용할 때 가장 높았다. flupyrazofos의 반수침투시간($PT_{50}$)은 배추좀나방에서는 0.731 시간(44분)이었고, 파밤나방에서는 0.504시간(30분)으로 나타나 배추좀나방보다 파밤나방에서 침투시간이 다소 빨랐고, 배설량도 배추좀나방보다 파밤나방에서 많았으며 배설되는 시간도 빨랐다.