【作者】 刘萍；

【导师】 周玲玲；

【作者基本信息】 石河子大学 ， 植物学， 2006， 硕士

【摘要】 大叶补血草Limonium. gmelinii (Willd.) Kuntze和耳叶补血草Limonium. otolepis (Schrenk) Kuntze是白花丹科(Plumbaginaceae)补血草属(Limonium)的泌盐盐生植物。本实验从营养器官结构和生理生化指标两方面对这2种补血草的耐盐性进行了研究,为建立植物耐盐性评价指标体系、筛选新疆耐盐植物种质资源、开发利用盐碱地提供一些资料。明确了两种补血草营养器官的耐盐结构特征,其中标志性特征是茎和叶片表皮分布有很多盐腺。表皮细胞排列紧密整齐,其外切向壁增厚,表皮外还被有很厚的角质层,有利于减少蒸腾;根中有大量通气组织,有利于氧气的输送和贮存。此外,还有一些结构,它们不与植物体耐盐直接相关,而是间接地通过加强同化、输导、机械支持能力来增强植物体的抗性,从而提高植物体在盐渍生境中的生活能力。在不同昼夜温度条件下用不同浓度NaCl(mmol/L)溶液及等渗聚乙二醇溶液处理2种补血草的种子,分别测定其萌发率、发芽势和发芽指数,测定处理9天未萌发的种子移入蒸馏水后的萌发恢复率,以研究温度、盐胁迫和模拟干旱胁迫对种子萌发的影响。结果表明:2种补血草种子萌发的最适温度为25/15℃,在蒸馏水中的萌发率最高,随着盐浓度和PEG6000溶液浓度的增加,种子的萌发率、发芽势和发芽指数递减,对萌发产生抑制作用;PEG6000溶液对种子的萌发抑制程度与等渗NaCl溶液相当。原来较高浓度下的种子具有较高的萌发恢复率。分别用不同浓度NaCl溶液处理大叶补血草和耳叶补血草的幼苗,各项生理生化指标的测定结果为:随着盐胁迫强度的增加,两种补血草的膜透性增大,脯氨酸(Pro)、可溶性总糖(SS)、游离氨基酸(AA)、有机酸(OA)和丙二醛(MDA)含量都呈增大的趋势。叶绿素(CHl)含量呈下降的趋势,叶绿素a与叶绿素b的比值(CHla/CHlb)变化趋势与含量变化趋势相反。超氧化物岐化酶(SOD)活性呈上升的趋势。两种补血草肉质程度变化为先升后降。更多还原

【Abstract】 Limonium. Gmelinii (Willd.) Kuntze and Limonium. Otolepis (Schrenk) Kuntze are recretohalophytes belong to Plumbaginaceae Limonium. In this essay, investigated the salt tolerance of two recretohalophytes in two aspects of microstructure and physiological indexes. The results of research could supply some information for establishing estimate indexes of salt tolerance of plants in order to filtrating resources of halophytes of Xinjiang and empoldering saline soil.The salt resistant structural characteristics of two species of Limonium were defined. The typical characteristics that a lot of salt glands distribute in epidermis of leaves and caulis . The arranged compactly epidermal cell had thick keratose layer and the thickness increment external tangential wall of epidermis cell which propitious to reducing water evaporation; There are well-developed aerenchyma foxming many air passages in cortex of roots is advantageous to the transport and store of oxygen, and so on.Moreover, there were some other structures that had not direct relationship with salt resistant function, but they enhanced the tolerance of the p lant through increasing the abilities of assimilating, transporting and sustaining.The seedlings of L.gmelinii and L.Otolepis were treated with different concentrations of NaCl .The results of physiological indexes showed that cell membrane permeability (CMP) of two species increased along with the increasing of NaCl concentration, and concentrations of proline(Pro), soluble sugar (SS), dissociative amino acid(AA), organic acid(OA) and malondialdehyde(MDA) showed the same tendency. The concentrations of chlorophyll (CHl) of two species decreased as the stress intensity extended, CHl a/CHl b value reduced when salt stress increased; the Superoxide dismutase(SOD) activity of two species increased along with the increasing of NaCl concentration. fleshy of two halophytes were increased firstly, and then gave a decreasing tendency when stress intensity extended.Seeds of L.gmelinii and L.Otolepis were germinated 9 days at different temperature regimes in different concentration NaCl solution and iso-osmotic PEG. According to the germination percentage, germination potential , germination index and the germination recovery percentage of seeds that were incubated in NaCl and PEG solutions for 9 days recovered after being transferred to distilled water. We can conclude that: A temperture regine of 15℃night and 25℃day yielded optimal germination. Germination p was highest in the distilled water. The germination percentage, germination potential and germination index increased along with the reducing of NaCl and iso-osmotic PEG concentrations, that had inhibitory effect on the germination of seeds. The inhibitory level of PEG as much as that of iso-osmotic NaCl.更多还原