Primisulfuron 또는 Imazethapyr와 Cytochrome P-450 저해제인 PBO의 혼합처리가 옥수수의 생장 및 ALS효소 활성에 미치는 영향을 조사한 결과는 다음과 같다. 1. Pioneer 3751 IR은 Primisulfuron과 Imazethapyr에 Imazethapyr에 높은 내성을 보인 반면, Pioneer 3751과 찰옥 2호는 감수성을 보였다. 2. Pioneer 3751 IR은 Primisulfuron과 PBO혼합처리에서 높은 저항성을 나타내어 PBO혼합처리에 따른 영향은 적었으나 Pioneer 3751,수원 118호와 찰옥 2호는 PBO혼합처리에 따라 생장 저해가 PBO무처리에 비해 높게 나타났다. 3. Pioneer 3751 IR의 생장은 Imazethapyr와 PBO 혼합처리에 따른 영향은 적었으며 Pioneer 3751과 수원 118호, 찰옥 2호는 생장저해가 심하였으나 PBO혼합처리 에 따른 약해 상승작용은 크지 않았다. 4. ALS효소 활성은 Prirnisulfuron은 $0.01{mu}M$에서부터, 그리고 Imazethapyr는 $1{mu}M$에서부터 Pioneer 3751 IR 품종을 제외한 3품종에서 현저하게 억제되었으며, Primisulfuron과 PBO혼합처리에 의하여 Pioneer 3751 IR과 Pioneer 3751에서는 활성저해가 더 크게 나타났고 수원 118호와 찰옥 2호에서는 차이가 없었으며, Imazethapyr와 PBO의 혼합처리에서는 4품종에서 모두 약간 억제되었다.
The combined effects of primisulfuron and imazethapyr treated with piperonyl butoxide(PBO) on growth inhibition and acetolactate synthase(ALS) activity in corn were studied to identify the tolerance mechanism among corn cultivars. Pioneer 3751 IR showed resistance to primisulfuron and imazethapyr, but Pioneer 3751 and Chalok 2 were susceptible to them. Pioneer 3751 IR was tolerant to primisulfuron regardless of PBO treatment, but Pioneer 3751, Suwon 118 and Chalok 2 were more greatly inhibited by combined treatment of primisulfuron with PBO. Synergistic effect on growth inhibition in Pioneer 3751 IR, Pioneer 3751, Suwon 118 and Chalok 2 was not occurred when imazethapyr was treated with PBO, but Pioneer 3751, Suwon 118 and Chalok 2 tended to inhibit by combined treatment of imazethapyr with PBO. Pioneer 3751 IR showed higher ALS activity than Pioneer 3751 when primisulfuron or imazethapyr was treated. ALS activity was inhibited by primisulfuron at $0.01{mu}M$ or above and imazethapyr at $1{mu}M$ or above, and inhibitory effect on ALS activity was observed by primisufuron and imazethapyr treatments with PBO.
