【作者】 王海清；

【导师】 徐柱；

【作者基本信息】 中国农业科学院 ， 草业科学， 2009， 硕士

【摘要】 本文以搜集自内蒙古、北京、宁夏、甘肃、新疆、青海及西藏7省区的披碱草属5种18份野生种质为材料,从形态特征、叶表皮特征和茎叶横切面解剖结构等方面作了深入细致的比较研究,主要研究结果如下:1.选用19个性状指标,对披碱草、圆柱披碱草、垂穗披碱草、麦宾草和老芒麦表型特征研究结果显示,旗叶长、旗叶宽、每穗轴小穗数、穗轴第一节间长、外稃芒长、颖长和颖芒长7个性状的变异系数较高,是披碱草属植物产生变异的主要性状。2.供试的5个种18份材料叶下表皮和横切面结构组成相同,表明披碱草属植物是一个自然分类群。但是叶下表皮细胞大小、气孔器大小、副卫细胞形状和垂周壁形态、主脉维管束高度、上表皮厚度、角质层厚度、叶中脉突起度及叶缘形状种间差异性显著(P<0.05),可将上述形态差异和量化指标作为披碱草属种间分类的依据之一。气孔指数、气孔长宽比可作为检测植物抗性强弱的依据之一。3.叶下表皮特征指标中,气孔器长度、气孔器宽度、长细胞长度及副卫细胞形状5个生态因子(海拔高度、经度、纬度、年均温度和年降雨量)具有不同程度相关性,其中,气孔器长度、长细胞长度、副卫细胞形状与纬度呈极显著正相关,气孔器宽度与海拔高度呈显著负相关。4. 2份不同来源麦宾草茎的结构比较,来自宁夏六盘山的材料,其茎内维管组织较来自新疆的材料发达,具有较强的输导和支持作用。与成熟期相比,抽穗期的茎横切面表现为组织分化不成熟,中部没有显示出髓腔。5.叶下表皮细胞中某些显著的形态差异,叶片横切面解剖结构中某些量化指标的差异,可尝试作为遗传标记,鉴别披碱草属植物种间和种内的遗传变异。更多还原

【Abstract】 In this study, 18 wild germplasm materials of 5 species of Elymus L. were collected from seven provinces such as Inner Mongolia, Ningxia, Gansu, Xinjiang, Qinghai and Tibet. Comparative studied were carried deeply and carefully from morphological characteristics, leaf epidermal features, transverse section structures of leaves and stems, the main results as follows:1. Phenotypic variation was assessed by measuring 19 characters to Elymus subiricus L., Elymus excelsus T., Elymus dahuricus T., Elymus cylindricus(Franch.)Honda and Elymus nutans. The results showed that the different characters had different variation, some characters including flag leaf length, flag leaf width, number of spikelet, the first internode length, lemma awn length, glume length, glume awn length had higher coefficient of variance than others. These seven features are the main variance characters.2. The anatomaical structures of leaves were the same among these species, comprised of leaf epidermal cells, leaf tissues and leaf veins. While vascular bundle diameter, upper epidermis thickness, cuticular thickness, midrib enation and the morphology of leaf margin had significant variation among species (P<0.05).3. The characteristics of lower epidermis cells of five species were familiar with regular shape and dense arrangement. While the size of lower epidermis cell and stomata apparatus, the morphology of subsidiary cell and anticlinal wall had significant variation among species(P<0.05). The morphological variation and quantitative parameters can be considered as the principle of the species classification of Elymus L., stomatal index and stomatal length as the parameters of Elymus L. resistance.4. Among the lower epidermis indices, stomata length, stomata width, the length of long cell and the shape of subsidiary cell had different correlation with five ecological factors, such as altitude, latitude, longitude, annual average temperature and annual precipitation. Stomata length, long cell length and the shape of subsidiary showed very significant positive correlation with latitudes, while stomata width showed significant negative correlation with altitude.5. Compared of stem anatomic structure of two Elymus excelsus T. from different source, the result showed that a material of Ningxia was better than anther of Xinjiang because of the Ningxia material having a strong vascular tissue. The strong vascular tissue leaded to a strong effect of transportation and support.Compared the heading stage with maturing stage of stem anatomic structure, it was showed some different characters. The stem transverse section of heading stage had some characters as followed. The outer had a leaf sheath transverse section which was wide and the immaturity tissue; the inside was the main stem transverse section which had undifferentiating vascular bundle; pith cavity did not exist in the middle stem.6. The main prominent morphological difference of leaf lower epidermic cell and the quantitative varivance indexs of the leaf transverse section can be tried as genetic mark to identifiy the intraspecific and interspecific genetic variation of Elymus L.更多还原