碱胁迫对唐古特白刺生长及叶片超微结构的影响  

Effects of alkali stress on the growth and ultrastructure of Nitraria tangutorum

作　　者：张慧芳 闫海冰[1] 冯帆 于兆友 杨秀清[1] ZHANG Huifang;YAN Haibing;FENG Fan;YU Zhaoyou;YANG Xiuqing(School of Forestry,Shanxi Agricultural University,030801,Taigu,Shanxi,China)

机构地区：[1]山西农业大学林学院,山西太谷030801

出　　处：《中国水土保持科学》2021年第1期35-42,共8页Science of Soil and Water Conservation

基　　金：山西省应用基础研究计划项目“白刺高耐盐代谢调控机理研究”(201901D111224);山西省重点研发计划项目“白刺耐盐机理应用研究及示范”(201703D221009-3);山西省科技攻关项目“晋北、晋西北丘陵风沙区白刺繁育与人工栽植技术研究”(20130311023-3)。

摘　　要：研究碱胁迫下唐古特白刺(Nitraria tangutorum)生长及叶片超微结构的变化,探讨其耐碱能力及耐碱机制,以期为实现唐古特白刺在抑制盐碱地土壤退化及实现盐碱化土壤的持续生物改良提供参考。采用不同浓度(200、300、400、500 mmol/L)的Na HCO3和Na2CO3混合溶液对唐古特白刺实生苗进行碱胁迫处理,分析测定其生长和生理指标,并使用透射电镜对其叶肉细胞超微结构进行观察和比较。结果表明:1)唐古特白刺株高、生物量、根系活力和叶绿素含量随碱胁迫浓度的增大而下降;丙二醛含量和电解质渗透率随碱胁迫浓度的增大而增大;叶片SOD、CAT活性和脯氨酸质量分数随碱胁迫浓度的增大呈先升后降的趋势。2)叶肉细胞细胞壁随碱浓度升高由透亮逐渐变得晦暗、不再光滑,出现沉淀或溶解趋势;细胞质膜褶皱突起呈形状各异的小泡;叶绿体肿胀变形,并伴随质壁分离,基粒片层紧致结构被破坏,部分类囊体排列散乱,出现囊泡化甚至解体;叶绿体外膜凹陷或局部破裂,基质外渗;叶绿体中嗜锇颗粒集聚成堆,数量、体积较对照都有增加且伴随少量淀粉粒出现。综上,低浓度碱胁迫对唐古特白刺生长具有一定抑制作用,≥300 mmol/L的碱胁迫浓度对白刺生长及叶片超微结构产生明显的抑制及损伤。碱胁迫下SOD、CAT活性和脯氨酸质量分数升高,嗜锇小体增多变大以及淀粉粒的出现,表明唐古特白刺对碱胁迫有较强的适应能力。[Background]Soil salinization has become a global problem of resources and environment,which has seriously restricted the growth of crops and the survival of vegetation such as forests and grass,and has broken the ecological balance and system stability. The changes of growth and leaf ultrastructure of Nitraria tangutorum under alkali stress were studied,and its alkali tolerance and alkali tolerance mechanism were discussed in order to provide reference for achieving N. tangutorum’s inhibition of soil degradation and sustainable biological improvement of salinized soil. [Methods]NaHCO3 and Na2 CO3 mixed solutions of different concentrations( 200,300,400,and 500 mmol/L) were used to treat the seedlings of N. tangutorum. The growth and physiological indexes of the seedlings were measured,and the ultrastructure of mesophyll cells was observed and compared by transmission electron microscopy. All data were subjected to ANOVA and Duncan’s multiple tests for each parameter at P < 0. 05 using R3. 3. 1. Parameter values were presented as means with standard error( n = 3). [Results]1) The plant height and biomass of N. tangutorum decreased with the increase of alkali stress concentration,and decreased significantly under 300 mmol/L stress. 2) Root activity and Chl( a + b) content decreased with the increase of alkali stress concentration. The former was more sensitive to alkali stress,and decreased significantly under 200 mmol/L stress. MDA content and electrolyte permeability in the leaves increased gradually with the increase of alkali stress concentration. SOD,CAT activity and proline content in the leaves increased at low concentration,but decreased at high concentration under alkali stress. The activity of SOD reached the maximum at 400 mmol/L under alkali stress,while the activity of CAT and the proline content reached the maximum at 300 mmol/L under alkali stress. 3) The ultrastructure showed that the cell wall of mesophyll cells gradually became dark and no longer smooth with the increase of alkali concentrati

关 键 词：唐古特白刺 叶肉细胞 超微结构 碱胁迫 

分 类 号：S793.9[农业科学—林木遗传育种]