稗草对7种除草剂的敏感性及其生物测定方法的研究

Study on susceptibility of barnyard grass(Echinochloa crusgalli) to 7 herbicides and their bioassay methods

应用滤纸法研究不同处理时间稗草(Echinochloa crusgalli)对7种除草剂的敏感性,并比较了稗草在滤纸法、琼脂法和盆栽喷雾法中对二氯喹啉酸的灵敏度,并应用琼脂法测定了7种除草剂的敏感性。结果表明:吡嘧磺隆(pyrazosulfuron-ethyl)以2 d的EC50值最低;五氟磺草胺(penoxsulam)、丙炔草酮(oxadiargyl)、二氯喹啉酸(quinclorac)和扑草净(prometryn)则以3 d的结果为最好;四唑酰草胺(fentrazamide)和嗪草酮(oxaziclomefone)以4 d的结果为最敏感。3种生物测定方法中稗草对二氯喹啉酸的敏感性以琼脂法为好,能达到快速、灵敏的目的。7种除草剂的敏感性大小(根据EC50值)顺序为:嗪草酮>四唑酰草胺>丙炔草酮>二氯喹啉酸>五氟磺草胺>吡嘧磺隆>扑草净。

The susceptibihty of barnyard grass to 7 herbicides was studied by filter paper method under the condition of different treating times, and the susceptibihty of barnyard grass to quinclorac was compared by three bioassay （ agar method, filter paper method, and pot-spraying method）, and the susceptibility of barnyard grass to 7 herbicides by agar method was tested. The result showed that the 2 days＇ EC50 of pyrazosulfuron-ethyl was lowest, the optimum time of treating barnyard grass by penoxsulam, oxadiargyl, quinclorac and prometryn was 3 days, the most susceptibility time of treating barnyard grass by fentrazamide and oxaziclomefone was 4 days. The agar method was a most rapid and delicacy method in three methods for determining the susceptibihty of barnyard grass to quinclorac. Based on the EC50, the susceptibility of barnyard grass to 7 herbicides by agar method was in the following order： oxaziclomefone 〉 fentrazamide 〉 oxadiargyl 〉 quinclorae 〉 penoxsulam 〉 pyrazosulfuron-ethyl 〉 prometryn.