助剂激健对甲基二磺隆防除抗精唑禾草灵菵草的增效作用

张健 高原 姜英 李茹 董立尧

摘要：旨在明确助剂激健（主要成分为非离子表面活性剂、油酸甲酯、玉米胚芽油、油茶籽油等）对甲基二磺隆防除抗精唑禾草灵菵草是否具有增效作用，并探究其最佳增效剂量及机制。采用室内整株生物测定法筛选激健对甲基二磺隆防除抗精唑禾草灵菵草的最佳增效剂量，并通过测定激健对药液表面张力、接触角、扩展直径、最大持留量等物理指标的影响，以及对抗精唑禾草灵菵草乙酰乳酸合酶（ALS）活性的影响，来阐明其增效作用机制。结果表明，助剂激健和甲基二磺隆的最佳增效组合为甲基二磺隆12 g a.i./hm2+激健0.05%（体积分数）;激健能显著降低药液的表面张力及接触角，显著增加扩展直径及最大持留量;激健对抗精唑禾草灵菵草ALS活性无显著影响。由结果可以看出，助剂激健对甲基二磺隆防除抗精唑禾草灵菵草具有增效作用，主要是通过改变药液理化性质而发挥增效作用，而不是在生理生化水平上对甲基二磺隆的靶标酶活性产生影响。

关键词：菵草;精唑禾草灵抗性;助剂激健;整株生物测定;小麦安全性;增效机制

中图分类号：S451.2  文献标志码：A  文章编号：1003-935X（2019）01-0056-08

Abstract：This study aims to clarify whether the adjuvant Jijian （whose main ingredients are non-ionic surfactant，methyloleate，corn germ oil，Camellia oleifera seed oil） has a synergistic effect on mesosulfuron-methyl for the control of fenoxaprop-P-ethyl-resistant Beckmannia syzigachne，andto determine the best synergistic dose and mechanism.Whole-plant bioassayswere used to screen the best synergistic dose of adjuvant Jijian;thesynergism mechanism was explored by testing the influence of Jijian on physical indexes such as surface tension，contactangle，expanded diameter and maximum retention of the pesticide liquid. The effect Jijian to ALS enzyme activity in fenoxaprop-P-ethyl-resistant B.syzigachnewas also tested. The best combination dose was mesosulfuron-methyl 12 g a.i./hm2+Jinjian 0.05% （V/V）. Jijian significantly reduced the surface tension and contact angle of the pesticide liquid while increasing the expanded diameter and the maximum retention. Jijianhad no significant effect on the ALS enzyme activity of fenoxaprop-P-ethyl-resistant B.syzigachne. Jijianhad a synergistic effect on mesosulfuron-methyl in controllingfenoxaprop-P-ethyl-resistant B.syzigachne. The synergistic effect was exerted mainly by changing the physicochemical properties of the herbicide liquid，with no affect on the activity of the target enzyme at the physiological and biochemical level.

Key words：Beckmannia syzigachne;fenoxaprop-P-ethyl-resistant;adjuvant;whole plant bioassay;safety to wheat;synergistic mechanism

精唑禾草靈为芳氧基苯氧基丙酸酯类（AOPPs）除草剂，其作用靶标为乙酰辅酶A羧化酶（ACCase），因其活性高、杀草谱广而被广泛用于小麦田防除一年生禾本科杂草。由于长期单一使用该除草剂，并逐年增加用量，从而导致其药效下降。张锁荣发现，菵草在连续多年使用精唑禾草灵后已对其产生了抗药性[1]。……