Abstract
This experiment was conducted to investigate the control effect of nuclear polyhedrosis virus and NeemAzal-T/S on Spodoptera litura larvae. In laboratory test, values of$ LT_{50}$ and $LT_{95}$ when treated with S. litura nuclear polyhedrosis virus (SINPV) $1$\times$10^{8}$ PIBs/ml plus NeemAzal-T/S 200 ppm were 1.94 and 8.33 days, respectively. Control effect of the combination of SINPV $1$\times$10^{8}$ plus NeemAzal-T/S 200 ppm was higher than the other concentrations. This mixed treatment could reduce LT$_{95}$ by 3 days. When SINPV alone was sprayed to the S. litura larvae reared on chinese cabbage seedling, the mortalities were 10.7~6.7% at 4 days after treatment. In combinations of SINPV plus NeemAzal-T/S at each level of concentration, the mortalities appeared faster and higher at 4 days after application than single treatment. Especially, the mortalities by combinations of SINPV $1$\times$10^{8}$ /PIBs/ml plus NeemAzal-T/S at 75~200 ppm were 100% at 9 days after treatment. The body weight of untreated larvae was increased 9.4-folds from 235 mg to 2194 mg after 7 days. However, the increasing levels of larval weight were 4.8- and 7.0-folds in the separate treatments of NeemAzal-T/S and SINPV, respectively. Whereas in the combinations of SINPV $10^{4~8}$ PIBs/ml plus NeemAzal-T/S 75~200 ppm, larval weight was increased 3.9 to 2.9-folds. These results showed that the mortality and inhibition of larval weight in the combination of SINPV and NeemAzal-T/S were highly enforced by synergistic effect.
담배거세미나방 방제를 위한 핵다각체병 바이러스와 NeemAzal-T/S의 혼합처리 효과는 다음과 같다. 인공사료에 혼합 처리하여 실내 검정한 결과 핵다각체병 바이러스$ 1$\times$10^{8}$ PIBs/ml과 NeemAzal-T/S ppm 혼합한 경우에 $LT_{50}$ 과 $LT_{95}$가 각각 1.94일과 8.33일로 다른 처리구보다 빠르게 나타났다. 핵다각체병 바이러스 $1$\times$10^{6~8}$ PIBs/ml과 NeemAzal-T/S ppm 혼합살포로 단독처리보다 $LT_{95}$에서 3일 정도의 살충기간을 단축할 수 있었다. 배추유묘에서의 병원성 검정 결과 바이러스 단독처리는 4일째의 살충율이 10.7~6.7%로 낮으나, 핵다각체병 바이러스와 NeemAzal-T/S혼합 처리시에 살충효과가 빠르고 살충율도 높게 나타났다. 특히 핵다각체병 바이러스 $1$\times$10^{8}$ PIBs/m1과 NeemAzal-T/S 75~200 ppm처리에서는 9일째에 100%의 살충율을 보였다. 핵다각체병 바이러스를 처리하지 않은 담배거세미나방 유충은 초기 235mg에서 7일째에 2,194 mg으로 9.4배의 체중이 증가하였다. NeemAzal-T/S 단독처리시에는 200 pprn에서 1,120mg으로 4.8배 체중이 증가하였으며 바이러스 단독처리에서는 $1$\times$10^{8}$ PIBs/ml에서 7.0배 증가하였다. 그러나 두처리를 혼합하면 7일째에 $SINPV1$\times$10^{4~8}$ /+NeemAzal 75~200 ppm에서 3.9~2.9배만이 증가하여 단독처리보다 체중증가가 둔화되어 혼합처리에 의한 상승효과가 있었다.
