PEG和低温胁迫对烟草幼苗某些生理特性的影响  

Effects of PEG and Chilling Stress on Some Physiological Characters of Tobacco Seedlings

作　　者：张燕[1] 方力[1] 姚照兵[2] 冯永新[2] 吴业池[2] 

机构地区：[1]云南烟草科学研究院生物技术重点实验室,云南昆明650106 [2]中国科学技术大学经济技术学院,安徽合肥230052

出　　处：《吉林农业大学学报》2002年第6期14-19,共6页Journal of Jilin Agricultural University

摘　　要：以NC89为试验材料,用不同浓度的聚乙二醇(PEG)溶液处理烟草种子,研究了在5℃低温胁迫下PEG对四叶期烟苗与抗冷性有关的某些生理生化特性的影响。结果表明:PEG浸种处理能提高低温胁迫条件下烟苗的存活率,烟苗中可溶性糖和脯氨酸含量分别增加了95.7％和161.8％;叶绿素含量、呼吸速率和核酸等含量均明显高于对照。低温胁迫期间,烟苗的超氧物歧化酶(SOD)、过氧化氢酶(CAT)等活性显著高于对照,其膜脂过氧化产物和质膜透性及O2-。含量均低于对照。20％PEG浸种处理对提高烟草幼苗膜系统稳定性及抗冷性物质含量有一定的作用。After submerging tobacco seeds(NC89) with different concentrations (0,20%) of PEG solution, seedlings of tetraphyllous phase were treated with temperature ( 5℃) for 1 - 5 days in order to probe into the effects of PEG on some physiological and biochemical characters related to chilling resistance in tobacco seedlings. The results showed that 20 % of PEG not only increased the survival rate of seedlings after chilling stress at 5℃ temperature, but also increased the content of soluble sugar by 95.7 % , and the content of proline by 161.8 % in tobacco seedling leaves. In comparison with the control, the content of chlorophyll and nucleic acid and respiratory rate in seedlings treated with PED all increased significantly under chilling stress. At the same time, activities of superoxide dismutase (SOD) , catalase( CAT) were kept at a high level in tobacco seedlings submerged with PEG than that of control seedlings . The level of malondialdehyde(MDA) in the seedlings and the relative permeability of membrane and the O2- . formation in tobacco seedlings decreased during the chilling stress. The changes of physiological index before and after the chilling stress showed that the index were closely related to the chilling resistance of seedlings. These results suggested that 20% PEG had an effect on stability of membranes and increased the content of protective substance for cold tolerance in tobacco seedlings under chilling stress.

关 键 词：PEG 低温胁迫 烟草 幼苗 生理特性 聚乙二醇 抗冷性 

分 类 号：S572[农业科学—烟草工业]