低温胁迫对马铃薯幼苗抗寒相关生理指标的影响

Effects of Low Temperature Stress on Physiological Indexes Related to Cold Resistance of Potato Seedlings

对5份马铃薯抗寒野生种Solanum commersonii(CM)材料及1份不抗寒栽培种Solanum phureja(DM)材料进行了抗寒性表型鉴定及相关生理指标的测定.结果表明:在低温胁迫下,CM中超氧化物歧化酶(SOD)活性显著增加,在-4℃处理6 h时达到峰值,而DM的SOD活性显著降低;脯氨酸含量在低温胁迫下整体呈现增加趋势,但抗寒材料中的含量显著高于不抗寒材料;过氧化物酶活性、可溶性蛋白含量和可溶性糖含量在低温胁迫后在多数材料中都有一定程度的增加,但不同材料响应模式不同,整体上抗寒种质的生理指标值普遍高于栽培种DM.研究结果表明CM可以通过提高SOD活性、脯氨酸含量和可溶性糖含量等来抵御寒冷.

This study was carried out on one cold sensitive cultivar and five wild cold resistant accessions.The physiological indexes and cold-resistant ability were evaluated in response to low temperature stress for cold resistant germplasm S.commersonii(CM)and non-cold-resistant cultivar DM.The results showed that the SOD activity of CM increased significantly under low temperature stress,and reached the peak at-4℃for 6 h,while the SOD activity of DM decreased significantly.Under low temperature stress,there was an overall increasing trend for the proline content,however,the changes of proline content in cold resistant accessions were significantly higher than the cold sensitive cultivar.Peroxidase activity,soluble protein,and soluble sugar contents for most of the accessions under low temperature stress had certain degree of changes,but the response patterns of different accessions were different.In conclusion,under low temperature stress,the physiological indexes of cold-resistant germplasm were generally higher than those of the cultivar DM,indicating that potato seedlings can resist cold by increasing SOD activity,proline,and soluble sugar contents.