Abstract: The seeds of eight species and varieties of barnyar dgrass were treated with pretilachlor. Differences in bud length, leaf cells length, coleoptile cells length, and α-amylases activities of barnyardgrass after the herbicide treatment were found among eight species and varieties of barnyardgrass. Control percentage of the herbicide to Echinochloa crusgalli var. mitis was the lowest, and E. colonum was the highest among the tested barnyardgrass. It seemed th at the different species and varieties of barnyardgrass have various tolerance to the pretilachlor.

Key words: Echinochloa, weed, pretilachlor, herbicide tol erance, herbicide

摘要： 2001年10月采集南京地区8种稗草（Echinochloa）种子，分别用0、0.01、0.10、1.00、10.00 mg/L扫茀特浸稗草种子,萌发后测定其形态、结构及α淀粉酶活性。结果表明,无芒稗的株高、叶片及叶鞘细胞的长度、α淀粉酶活性受扫茀特抑制的程度最低,旱稗、稗、西来稗次之,光头稗最高。说明不同稗草的种及变种间存在耐药性的差异,其中无芒稗的耐药性最强,光头稗最弱。关键词:

关键词: 稗草, 杂草, 扫茀特, 耐药性, 除草剂