The sensitivity of different maize varieties to the nicosulfuron

chinois. 烟嘧磺隆是玉米田重要的芽后除草剂，采用温室盆栽和皿内生测法比较了32种不同玉米品种对烟嘧磺隆的敏感性差异。温室盆栽测定结果表明，在烟嘧磺隆大田常规用量60g/hm2下，各品种对药剂的敏感性差异显著，泰玉2号（正交）、金珍珠、泰玉15号、紫糯等7个品种对烟嘧磺隆表现较为敏感，株高抑制率均在40.4%以上，鲜重抑制率在31.37%以上，表现为植株生长受到抑制、叶片黄化、新叶牛尾状扭曲不能正常抽出；淄玉2号、泰玉2号（反交）、聊玉18、鲁原单33、鲁原单14、郑单958等品种的株高抑制率在30.6%～38.1%，敏感性略低，植株外部形态无明显变化；而农大2008、农大108、鑫玉958和泰玉12号生长正常，耐药性相对较高，无明显药害症状。其它品种介于豫单2002和鑫玉958之间。皿内生测法测定表明，烟嘧磺隆对玉米幼苗主根长的抑制存在较大差异，根据IC50值，各品种敏感性依次为：泰玉2号（正交）金珍珠泰玉7号紫糯泰玉2号（反交）泰玉15费玉5号新单23户单2000聊玉19泰玉12鲁原单33聊玉18农大108农大2008。

anglais. Nicosulfuron is an important herbicide used for maize. The sensitivity of 32 maize varieties to nicosulfuron was studied and this result could provide some warranty for using of nicosulfuron. With the method of planting in pot, the effect of nicosulfuron to maize in seedling was observed. The results showed that with the normal dosage 60g/hm2, inhibiting rate of the plant height and weight of Taiyu 2　(zhengjiao), Jinzhenzhu, Taiyu 15, Zinuo and other three breeds are beyond 40.4% and 31.37%, and it is obvious that plant growing is inhibited, the leaves etiolate and new leaves twist severely and couldn’t grow normally. Inhibiting rate of the plant height of Ziyu 2, Taiyu 2　(fanjiao), Liaoyu 18, Luyuandan 33, Zhengdan 958 and some other varieties are between 30.6% and 38.1%, the sensitivity of these varieties are lower and the plant modalities are not influenced bigger; in addition, Nongda 2008, Nongda 108, Xinyu 958 and Taiyu 12 grow healthy, the resistance to nicosulfuron are higher compared with other varieties. There aren’t clear injury symptoms on these plants. And the sensitive degree of other varieties is between Yudan 2002 and Xinyu 958. Finally, with bioassay method in foster utensil, sensitivity of the maize root length to nicosulfuron is detected: based on IC50, the sensitivity order is: Taiyu 2(zhengjiao)JinzhenzhuTaiyu 7ZinuoTaiyu 2(fanjiao)Taiyu 15Feiyu 5Xindan 23Hudan 2000Liaoyu 19Taiyu 12Luyuandan 33Liaoyu 18Nongda 108Nongda 2008.