【作者】 刘兴亮；

【导师】 王崑；

【作者基本信息】 东北农业大学 ， 园林植物与观赏园艺， 2010， 硕士

【摘要】 白刺(Nitraria L.)为蒺藜科的小灌木,其适应性强,极耐盐碱,覆盖能力极强,是盐碱地治理和防风固沙的先锋树种。本试验通过盆栽试验方法,以唐古特白刺和西伯利亚白刺为材料,用四种单盐和不同配比的混合盐处理,对白刺在盐碱胁迫下生理适应性的变化进行深入研究,为研究白刺的耐盐适应性提供依据,为其在盐碱地区推广,丰富城市绿化树种提供依据。利用植物生理与生态学的技术手段,分析了在不同浓度、pH的盐碱胁迫对两种白刺生理学特性的影响,结果表明:1、盐碱胁迫对两种白刺生长特性的影响研究表明:一定的盐胁迫会促进白刺叶绿素的合成,同时提高白刺的根系活力,只有在混合盐碱胁迫下盐浓度大于300mmol/L,pH>10.59条件下,其叶片叶绿素含量略有下降,并伴随着根系活力的降低,开始影响白刺正常的同化作用;四种单盐胁迫下,两种白刺只有在400mmol/LNa2CO3、pH11.68处理下叶绿素含量才略低于对照,根系活力却依然高于对照,对两种白刺的正常生长影响不大。2、盐碱胁迫对两种白刺膜系统影响的研究表明:两种白刺叶片经混合盐碱胁迫和四种单盐胁迫后电解质外渗率加大,膜脂过氧化物MDA含量总体增加,表明盐碱胁迫对膜系统产生了一定的伤害。不同盐碱胁迫下,电解质外渗率虽然高,但叶片结构并没有发生明显变化,植株没有死亡,可见两种白刺均具有较强的耐盐碱性。3、盐碱胁迫对两种白刺渗透调节物质的影响研究表明:混合盐碱胁迫下,两种白刺在盐浓度300mmol/L,pH<10.59的混合盐碱胁迫下,叶片渗透调节物质可溶性糖含量、可溶性蛋白、脯氨酸含量均有所提高;,盐浓度低于400mmol/L、pH低于11.68的四种单盐胁迫下,两种白刺叶片内渗透调节物质同样有一定的升高,说明不同的盐碱胁迫下,两种白刺都通过提高体内渗透调节物质的含量来增加细胞液浓度,维持了白刺叶片的正常水势,以提高白刺抵抗盐碱胁迫的能力,渗透调节物质含量的提高对白刺的耐盐性的提高有着积极意义。4、盐碱胁迫对两种白刺保护酶系统的影响研究表明:两种白刺保护酶活性在混合盐碱胁迫下,随着盐度和pH的增加而先上升后下降,而在单盐胁迫下,随着盐度和pH的增大,SOD活性和CAT活性保持上升的变化趋势,POD活性呈现先升高后下降的变化,因此在不同的盐碱胁迫条件下,白刺细胞内保护酶系统使自由基维持在一个低水平上,从而防止自由基对细胞的伤害,是两种白刺都可以适应较高盐碱环境的盐碱胁迫。5、较单盐胁迫,混合盐碱胁迫对植物的危害更大,白刺生理变化不仅受到浓度度的影响, pH也是一个重要的影响因素。对白刺生长有重要影响的盐浓度、pH、[CO32-]和[HCO3-]四个胁迫因素进行线性回归分析,除白刺叶绿素含量和根系活力不与四胁迫因素呈显著线性关系外,其余生理生化指标均与4胁迫因素呈线性关系(相关系数均R2>0.75),对四胁迫因素进行排序,盐浓度是最重要的胁迫因素。更多还原

【Abstract】 Nitraria L.is a shurb of zygophyllaceae, is the Tertiary Period relic plant. Nitraria L. is the fine cover plant anti saline-alkaline and the sand fixation pioneer plant which has strong adaptability, strong salt-tolerance, strong covering power.In this experiment testing,using Nitraria tangutorum and Nitraria sibirica as experiment materials,and it is using four single salt and different proportions complex saline-alkali stress, and it carries on deeply research of the changes of saline-alkali stress on physiological adaptability of Nitraria L., bases on combing predecessor’s research methods and results. It provides bases for researching salt-tolerant adaptability of Nitraria L.and popularizing Nitraria L. in saline-alkali area and riching urban greening tree species.This article utilized the plant physiological ecological research methods to analyze the physiology characteristic’s responds of two species of Nitraria L. under saline-alkali stress with different salinity and alkalinity. The results indicated that:1. The research of saline-alkali stress on growth characteristics of two species of Nitraria L. showed that: A certain saline-alkali stress would promote chlorophyll synthesis of Nitraria L., and at the same time increase their root vitality. Just only when salinity was higher than 300mmol/L, pH>10.59, the chlorophyll contents decreased slightly and along with the root vitality decline, it began to affect Nitraria’s normal anabolism; For four single salt stress, only under 400mmol/LNa2CO3, pH11.68 treatments , chlorophyll content of Nitraria L is slightly lower than the control, and the root activity is still higher than the control, the two species of Nitraria L prickly little effect on normal growth..2. The research of saline-alkali stress on membrane systems of two species of Nitraria L. showed that: Under complex saline-alkali and four sigle salt stress, the electrolyte leakage rates in leaves of two species of Nitraria L. increased, resulted in membrane lipid peroxidation produce - MDA contents increased, it showed that saline-alkali stress made certain damage to membrane systems. Under saline-alkali stess, the electrolyte leakage rates were high, but the structure of leaves didn’t change obviously, the plants were alive, it could clearly be seen, the two species of Nitraria L. had strong salt tolerance.3. The research of saline-alkali stress on osmoregulation substances of two species of Nitraria L. showed that: Under the complex saline-alkali stress of salinity 300mmol/L, pH<10.59, the contents of soluble sugar, soluble protein and proline increased in leaves of two species of Nitraria L.; Under the four salt stress of salinity 400mmol/L, pH<11.69, the contents of Osmotic adjustment increased in leaves of two species of Nitraria L.also, it shows: under the different salt stress, two species of Nitraria L. are increasing the content of osmolytes adjustment for increasing cell concentration,and provided leaves’normal water potential to enhance Nitraria’s saline-alkali resistance ability. The increase of osmoregulation substance content has a positive significance to improve Nitraria’s salt tolerance.4. The research of saline-alkali stress on protective enzyme systems of two species of Nitraria L. showed that: Under the complex saline-alkali stress, two species Nitraria L. of protective enzymes decreased with the increase of salinity and pH increased ,and then while in single-salt stress, with the increase of salinity and pH, SOD activity and CAT activity maintain the upward trend, POD activity increased firstly and then decreased to a change in the different salt stress conditions, the Nitraria L. cells to free radical protective enzyme system remains at a low level in order to prevent free radical cellinjury, are Nitraria L. thorn can be adapted to high saline environment salinity stress.5. Than the single-salt stress, alkaline stress on plants more dangerous, not only by physiological changes of Nitraria L degree of concentration, pH is also an important factors. Carried on linear regression analysis to salinity, pH, [CO32-] and [HCO3-] four stress factors which heavily influenced Nitraria’s growth, the chlorophyll content and root vitality in Nitraria weren’t remarkable linear with four stress factors, and the other physiological biological indices with the four stress factors all showed a linear relationship (correlation coefficient R2>0.75), sorting to four stress factors, salinity was the most important stress factor.更多还原