除草剂普杀特（Imazethapyr）对玉米根尖蛋白质和DNA合成的影响

除草剂普杀特（Ｉｍａｚｅｔｈａｐｙｒ）对玉米根尖蛋白质和ＤＮＡ合成的影响刘支前（北京农业大学农业应用化学系，北京１０００９４）关键词：普杀特，玉米，蛋白质，ＤＮＡ８０年代美国氰胺公司开发的咪唑淋酮类除草剂，由于其高效低毒、杀草谱广，又因对某些农作物具...

Effect of Imazethapyr on the Protein and DNA Synthesis in Maize Root Tips

Imazethapyr, an imidazolinone herbicide,at a concentration higher than 10-7 mol/L inhibited strongly the growth of maize seedlings (Fig.2).Protein synthesis,measured by 3 Halanine incorporation, was not inhibited (Tabs 1),while DNA synthesis,determined by 3 H-thymidine incorporation, was severely(60%) inhibited 24 h after the application of 10-5 mol/L of Imazethapyr(Table 2). An exogenous supply of leucine,isoleucine and valine(1 mmol/L each) to maize seedlings as a root drench prevented the inhibition of both growth and DNA synthesis caused by Imazethapyr(Fig.3,Table 3).The results indicate that the biosynthesis of leucine, isoleucine and valine is the sole site of action of Imazethapyr and suggest that the 3branched-chain amino acids play special roles in DNA synthesis during the interphase of plant cell cycle.