棉花品系Ｙ18对草甘瞵应激反应机理的研究

5-烯醇丙酮酰-莽草酸-3-磷酸合成酶（5-enolpyruvyl-shikimate-3-phosphate synthase, EPSPS）是植物和微生物体内合成芳香族氨基酸所必需的一个关键酶，但此酶受广谱性除草剂草甘膦的强烈抑制。本试验对草甘膦胁迫下的棉花品系（Y18）研究发现：棉花品系Y18具有两个不同的5-烯醇丙酮酰-莽草酸-3-磷酸合成酶基因epsps1和epsps2，两个基因的编码区与其他植物的epsps基因具有较高的同源性，在草甘膦胁迫作用下，棉花的epsps1基因表达较为稳定，epsps2基因表达提高了1.85-2.3倍，初步认为epsps基因表达量的提高是生物对胁迫作用的一种应激反应。

Research on the mechanism of the cotton Y18 cell line resistant to herbicide glyphosate

5-enol-Pyruvylshikimate -3-phosphate synthase (EPSPS) is an enzyme on the pathway toward the synthesis of aromatic amino acids in plants and microorganism, it also is the target of the broad-spectrum herbicide glyphosate。there were two distinct epsps genes: epsps1 and epsps2. and they had a high homologious with others epsps genes. The result of experiment suggest the expression of gene epsps1 maitained invariance in the stress of glyphosate, While expression of gene epsps2 in stress of glyphosate of glyphosate became 1.8 to 2.3 times than expression of non-glyphosate induced. we consider that it is a stress response of plant when it is in the stress of glyphosate。