4种稗属杂草对二氯喹啉酸等常用除稗剂的抗药性

Resistance of Four Species of Echinochloa to Quinclorac

稗属(Echinochloa spp.)杂草严重影响我国水稻安全生产。二氯喹啉酸作为主要的除稗剂,连续施用多年,抗性问题突出。为进一步探明稗草对二氯喹啉酸等除稗剂的抗性现状,以便有针对性地进行抗性治理,对采集于江苏省稻区的稗草种群进行抗性分析。结果表明,采自常州市金坛区金城镇、南京市六合区和镇江市句容市的稗草种群对二氯喹啉酸抗性频率分别为25.93%、30.53%和22.6%,采集于其他几个地区的稗草种群抗性频率在4.69%~9.71%之间。对分离筛选到4种抗性稗草进行抗性水平测定,整株生物测定结果表明,普通稗EB-S和EB-R的GR 50(生长抑制中量)值分别为194.85和4483.33 g a.i./hm 2,普通稗抗性材料(EB-R)的抗性指数达到了23,EB-R对二氯喹啉酸产生了较高水平的抗药性。孔雀稗(ES-R)、西来稗(EZ-R)和无芒稗(EM-R)对二氯喹啉酸的抗性指数分别为8.87、9.32、7.41,处于中等水平抗药性。另外,普通稗(EB-R)和西来稗(EZ-R)对双草醚和氰氟草酯产生了一定的抗(耐)药性,无芒稗(EM-R)对唑酰草胺产生了一定的抗(耐)药性。本研究结果可为通过轮换用药治理抗性杂草提供理论依据。

Echinochloa spp.have serious impacts on China s rice production.Quinclorac,as an effective herbicide,has been used for controlling Echinochloa spp.for many years worldwide,but quinclorac-resistant populations of Echinochloa spp.have become very serious.To further investigate the resistance status of Echinochloa spp.to quinclorac,Echinochloa spp.populations were collected in different rice-planting areas in Jiangsu Province.Quinclorac-resistance frequencies in Jincheng Town,Jintan District of Changzhou City,Luhe District of Nanjing City and Jurong City of Zhenjiang City were 26%,30%and 23%,respectively,while those from other districts ranged from only 4.7%to 9.7%.Moreover,the resistance levels of four Echinochloa species(Echinochloa crusgalli,Echinochloa crusgalli var.zelayensis,Echinochloa cruspavonis,Echinochloa crusgalli var.mitis)to quinclorac were determined.GR 50 values derived from whole plant bioassays for EB-S and EB-R populations were 195 and 4483 g a.i./hm 2,respectively.EB-R evolved a high resistance level to quinclorac with a resistance index(RI)of 23,while ES-R,EZ-R and EM-R were moderately resistant with RIs of 8.9,9.3 and 7.4,respectively.In addition,EB-R and EZ-R had also evolved resistance to bispyribac-sodium and cyhalofop-butyl,and EM-R to metamifop.The results will provide a theoretical basis for control of resistant weeds by rotating herbicides.