ALS저해형 제초제 imazethapyr와 primisulfuron에 내성인 고추품종을 선발하기 위하여 42종 고추품종을 공시하여 고추의 약해, 초장, 생체중 및 건물중을 측정하여 품종 반응을 조사하였다. 1. 레드탑, 해피드라이, 골든 타워, 하교레 품종은 imazethapyr에 내성을, 코리아, 조양, 오리엔탈 글로리, 하남 품종은 감수성을 나타냈다. 레드혼, 조풍, 광복, 왕조는 primisulfuron에 내성을, 코리아, 다홍, 참조아, 풍천 품종은 감수성을 나타냈다. 2. Imazethapyr에 대한 $I_{50}$ 농도는 감수성 품종은 0.075kg/ha, 내성품종은 0.20kg/ha이며, primisulfuron의 경우, 감수성 품종은 0.065kg/ha, 내성품종은 0.16kg/ha이었다. 3. Imazethapyr 처리에 따른 $GR_{50}$을 감수성 품종에서 0.05kg/ha, 내쟁품종에서 0.20kg/ha이며 primisulfuron 처리의 경우 감수성 품종은 0.07kg/ha, 내성품종은 0.16kg/ha이었다. 4. 따라서 ALS저해형 제초제에 대한 내수성품종과 감수성 품종간 내성 정도는 imazethapyr에서 3~4배, primisulfuron에서는 2~3배 차이를 나타냈다.
Selection of pepper (Capsicum sp.) cultivars tolerant to acetolactate synthase (ALS)-inhibiting herbicides {imazethapyr, 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3=pyridine-carboxylic acid, and primisulfuron methyl 2-[[[[[4,6-bis(difluoromethoxy)-2-pyrimidinyl]amino] carbonyl]amino]sulfonyl]benzoate} was investigated. Pepper cultivars such as Red Top, Happy Dry, Golden Tower, and Hagyeorae showed relatively tolerant response to imazethapyr, while cultivars; Korea, Cheongyang, Oriental Glory, and Hanam were susceptible. Red Horn, Jopoong, Kwangbok, and Wangcho cultivars were tolerant to primisulfuron whereas Korea, Dahhong, Chamjoah, and Poongchon cultivars were susceptible. Determination of growth inhibition by ALS-inhibiting herbicides showed that the $I_{50}$ estimates of growth from the susceptible- and tolerant-cultivars were 0.075 and 0.20kg ai/ha for imazethapyr; 0.06 and 0.16kg ai/ha for primisulfuron, respectively. Furthermore, the $GR_{50}$ estimates of growth from the susceptible and tolerant cultivars were 0.05 and 0.20kg ai/ha for imazethapyr; 0.07 and 0.16kg ai/ha for primisulfuron, respectively. This result, based on the $GR_{50}$ and $I_{50}$ values, indicates that responses of pepper to ALS-inhibiting herbicides between tolerant- and susceptible-cultivars were different about 3- to 4-fold to imazethapyr, and 2- to 3-fold to primisulfuron.
