硅对盐胁迫下枣组培苗生根培养效果、体内离子稳态及膜脂过氧化的影响  

Effects of Si onIn VitroRooting Culture Efficiency,Ionic Homeostasis and Membrane Lipid Peroxidation in Plantlets of Ziziphus jujuba Mill.under Salt Stress

作　　者：徐呈祥[1,2] 马艳萍[1] 尚旭岚[2] 徐锡增[2] 

机构地区：[1]肇庆学院生命科学学院,肇庆526061 [2]南京林业大学森林资源与环境学院

出　　处：《中国南方果树》2011年第4期19-23,共5页South China Fruits

基　　金：江苏省博士后科研计划(0701039B);中国博士后科学基金(20070411057)资助

摘　　要：以泗洪大枣微茎段增殖扩繁苗为试材,研究了NaCl 75 mmol/L胁迫下生根培养基中加Si(K2SiO30.75 mmol/L)与否对枣树组培苗生根培养效果、体内离子稳态及膜脂过氧化的影响。结果表明:盐胁迫下枣树微茎段外植体成活率和生根率显著降低,生根枣苗的侧根条数、侧根平均长度、株高和单株重量均显著减小,盐胁迫下加Si处理的这些指标则显著升高或增大而与对照无显著性差异。盐胁迫下枣树组培苗体内Na+、Cl-含量均较对照显著升高,K+/Na+显著减小;盐胁迫下加Si枣苗体内Cl-含量减少,与对照无显著差异;Na+含量和K+/Na+虽然显著高于对照,但显著低于不加Si处理。盐胁迫下生根培养基中加Si与不加Si相比,枣树组培苗体内谷胱甘肽过氧化物酶(GPX)等抗氧化酶系统应激响应明显趋于平缓,细胞质膜透性显著减小,丙二醛(MDA)含量则无显著差异。说明,盐胁迫下加Si优化枣树生根培养基条件,增强组培枣苗对盐分离子的选择性吸收功能,利于保持盐胁迫下枣树组培苗体内的离子稳态,诱导对膜脂过氧化作用抗性的提高。Using micropropagated ＇Sihongdazao＇ stems as explants,we studied the effects of adding soluble Silicon（Si）（0.75 mmol/L K2SiO3）into culture medium（1/2MS medium ＋0.01 mg/L 6-BA＋2.0 mg/L IBA ＋0.5 mg/L IAA） on rooting efficiency,salt ionic homeostasis and resistance to lipid peroxidation of in vitro plantlets of Chinese date（Ziziphus jujuba Mill.） under salt stress（75 mmol/LNaCl）.The results showed that survival rate and rooting rate of the explants,the number and length of the lateral roots,and the height and fresh weight of the regenerated plantlets were significantly decreased under salt stress,but these parameters were improved,when Si was added,to no significant difference compared with control.Levels of Na＋ and Cl-were significantly increased and the K＋/Na＋ ratio was significantly decreased in the plantlets by salt stress without Si.However,when Si was added,levels of Na＋ and Cl-were significantly reduced and the K＋/Na＋ ratio was significantly increased in salt stressed plantlets,though the content of Na＋ in the plantlets was still significantly higher and the content of Cl-and the K＋/Na＋ ratio were not significantly different from those of the control.Moreover,malonaldehyde（MDA） content and plasmalemma permeability of the plantlets were significantly lowered under salt stress by adding Si.Responses of superoxide dismutase（SOD）,catalase（CAT）,ascorbic acid peroxidase（APX） and glutathione peroxidase（GPX） activities in the plantlets suffering from salt stress became less fluctuated with the addition of Si.It indicated that adding an appropriate amount of soluble Si optimized rooting medium conditions and enhanced selective absorption of the plantlets to salt ions.This study showed the importance of Si in stabilizing salt ionic homeostasis and increasing resistance to lipid peroxidation of the plantlets under salt stress.

关 键 词：枣树 盐胁迫 硅 生根培养 离子稳态 膜脂过氧化 

分 类 号：S665.1[农业科学—果树学]