致死剂量咪唑乙烟酸处理对冀谷25苗期生理生化特性的影响

Effects of Lethal Dose of Imazethapyr on Physiological and Biochemical Characteristics of Jigu25 at Seedling Stage

为探究谷子品种冀谷25的除草剂致死剂量,并研究除草剂对其生理生化特性的影响,以冀谷25为试验材料,采用育苗盘培养方法,利用不同浓度除草剂咪唑乙烟酸处理3叶期谷子幼苗,在不同处理浓度和时间下,筛选出冀谷25幼苗的致死剂量;同时测定谷子幼苗在除草剂处理后叶绿素含量、电解质渗透率、丙二醛(MDA)含量、过氧化物酶(POD)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性等生理指标的变化。结果表明,谷子幼苗除草剂咪唑乙烟酸的致死剂量为3 375 mL/hm^(2),同时发现随除草剂浓度(2 250、3 375、4 500 mL/hm^(2))的升高和处理时间的延长,谷子幼苗的相应生理指标叶绿素含量、电解质渗透率、MDA含量、POD、SOD和CAT活性与对照相比在不同时间节点出现显著变化。研究结果显示,在喷施致死剂量的3 375 mL/hm^(2)的咪唑乙烟酸后,谷子幼苗受到胁迫从而启动生理保护机制。

In order to investigate the lethal dose of herbicide and its effect on physiological and biochemical characteristics of foxtail millet,in this study,three-leaf stage Jigu25 seedlings were treated with different concentrations of imazethapyr in seedling tray culture.The lethal dose of imazethapyr on Jigu25 seedlings was screened under different treatment concentrations and time.At the same time,the changes of chlorophyll content,electrolyte permeability,malondialdehyde(MDA)content,peroxidase(POD),superoxide dismutase(SOD)and catalase(CAT)activities of foxtail millet seedlings after imazethapyr treatment were measured.The results showed that the lethal dose of imazethapyr on Jigu25 seedlings was 3375 mL/ha,and it was found that with the increase of herbicide concentration(2250,3375,and 4500 mL/ha)and the extension of treatment time,the corresponding physiological indexes of chlorophyll content,electrolyte permeability,MDA content,POD,SOD and CAT activities of Jigu25 seedlings showed significant changes at different time compared with the control.This study showed that after spraying a lethal dose of 3375 mL/ha of imazethapyr,foxtail millet seedlings were subjected to stress and physiological protection mechanism was activated.