冷冻胁迫对毛竹幼苗生理代谢及抗寒相关转录因子表达的影响

Effects of Chilling and Freezing Stress on the Physiological Metabolism and the Expression of Cold-related Transcription Factors in Seedlings of Phyllostachys heterocycla cv. pubescens

试验以萌发90 d的毛竹幼苗为材料,研究冷冻胁迫(4℃和-10℃)下毛竹叶片抗氧化物酶(CAT、POD、APX和CAT)活性和渗透调节物质的变化及对抗寒相关转录因子表达的影响。结果表明,4℃和-10℃处理下,与对照相比,毛竹幼苗SOD和CAT酶活性下降,而POD及APX酶活性升高;可溶性糖和游离脯氨酸含量下降,但可溶性蛋白含量和MDA含量变化不明显。抗寒相关转录因子CBF1和DREB1表达量下降,而MYB和WRKY表达量上升。对胁迫下的毛竹幼苗生理代谢指标及抗寒相关转录因子表达量进行相关性分析,结果表明,只有WRKY表达量与POD和APX酶活性呈显著正相关关系,与可溶性蛋白含量呈极显著负相关关系。

Using the 90-day old seedlings of Phyllostachys heterocycla cv. pubescens as material,under the chilling( 4℃) and freezing(- 10℃) stress,the changes of antioxidant enzymes( CAT,POD,APX and CAT) activities,osmotic adjustment,and expression level of cold-related transcription factors were studied. In comparison with the untreated control,the results showed that the activities of SOD and CAT decreased,while that of POD and APX increased. The contents of soluble sugar and free proline decreased,whereas the changes of soluble protein and MDA contents were not significant. The expression level of CBF1 and DREB1 decreased,while that of MYB and WRKY increased. Multivariate correlation analysis showed that the WRKY expression was positively correlated with POD and APX enzyme activities and negatively correlated with the soluble protein content.