中文摘要：

以抗旱性较强的玉米品种‘鲁单50’幼苗为材料,采用等渗的离子胁迫（0.8% NaCl,-0.6 MPa）和非离子胁迫（20%PEG）进行渗透胁迫处理,从受胁迫的玉米幼苗根系中分离出63.5 kD热稳定蛋白.用水杨酸（SA）处理幼苗96 h,取材进行SDS-PAGE电泳,发现63.5 kD热稳定蛋白既可被渗透胁迫诱导,也可被SA诱导产生,且SA对非离子渗透胁迫和离子渗透胁迫下诱导的该蛋白的表达表现出不同的作用,SA对非离子渗透胁迫下该蛋白的表达有抑制作用,而对离子渗透胁迫下该蛋白的表达有促进作用.SA对非离子渗透胁迫或离子渗透胁迫＋ABA处理下的该蛋白的表达都表现出促进作用.研究表明,63.5 kD热稳定蛋白受SA信号途径的调控,并且在不同条件下,SA在参与和影响代谢过程的信号途径及其对代谢调控的机理可能存在差异.

英文摘要：

The roots of maize seedling（Zea rnays） were cultivated by solution in the mode of simulated isotonic ionic and nonionic osmotic stress by NaC1 （0.8%） and PEG （20%）,respectively. A heat-stable protein with 63.5 kD was separated from the maize seedling roots. Under different treatments,the analysis of heat-stable proteins by SDS-PAGE showed that the 63.5 kD protein was induced by osmotic stress or sali cylic acid （SA）. Moreover,the regulation by SA under nonionic stress was different from that under ionic stress. The results suggested that under nonionic stress SA restrained its expression,and under ionic stress SA enhanced it. We also found that SA enhanced the expression of 63.5 kD heat-stable protein under dif ferent osmotic stress and ABA. The results indicated that SA signal played some role in regulating the expression of 63.5 kD heat-stable protein, the effect of SA has diversity in participating the signal pathway and affecting mechanisms in plant metabolism under different conditions.