【作者】 杨美凌；

【导师】 方炎明；

【作者基本信息】 南京林业大学 ， 植物学， 2010， 硕士

【摘要】 本文以落羽杉属种及杂种为实验材料,通过物候、光合色素、形态特征和叶片解剖结构对种及品种的生理和形态特征进行了观察和分析,为落羽杉属品种鉴定提供了科学依据。得到如下主要结果:⑴通过物候观察和光合色素测定,将其物候划分为4类:早萌芽展叶迟落叶型,早萌芽展叶早落叶型,晚萌芽展叶早落叶型和中间型。叶绿素总量表现为上升-下降-上升-下降趋势,类胡萝卜素含量总体表现为下降-上升-下降趋势。⑵叶表皮显微和扫描电镜观察表明:叶片为双面气孔型。上表皮气孔数目和行列一般比下表皮少。非气孔分布区内,表皮细胞纵向行列,长方形或近长方形,表皮细胞壁直或呈微波状。气孔分布区内表皮细胞有时为不规则四边形或多边形,有时细胞被挤压变得扁平。角质层平周壁上有密集的簇晶状或块状附属物,无表皮毛。气孔器椭圆形,保卫细胞具极层结构,气孔器类型为双环型。各指标测定有极显著性差异,可作为品种鉴定指标。⑶落羽杉属树种的叶片横切面:由上表皮、上栅栏组织、海绵组织、下栅栏组织和下表皮组成。叶横截面形状不同:呈长棒状、不规则、倒“W”和“∞”字形,可作为分类依据。从生物学特性看本属植物性喜阴湿。从解剖学特征看落羽杉属树木的叶都为等面叶。各指标测定结果显示均有极显著性差异。⑷本文对落羽杉属树种及杂种的形态变异进行了聚类分析,编制了落羽杉属树种及杂种的形态识别检索表。更多还原

【Abstract】 In this paper, Taxodium species and hybrids were selected as experimental materials. Physiological and morphological features, e.g. phenology, photosynthetic pigments, morphology and leaf anatomy, of the species and varieties were observed and analyzed, in order to provide a scientific basis for identification of Taxodium varieties. The main conclusions as followe:⑴The results by phenological observation and photosynthetic pigment determination indicated that their phenologies were divided into 4 categories:①early sprouting and leaf-unfolding—late defoliation,②early sprouting and leaf-unfolding—early defoliation,③late sprouting and leaf-unfolding—early defoliation, and④intermediate type. The content dynamics of total chlorophyll follows a pattern of‘up—down—up—down’, for the carotenoid,‘down—up—down’.⑵Observation of leaf epidermis by microscopy and scanning electron microscope showed that the leaf was amphistomatic. The number and ranks of stomatas on upper epidermis were generally less than that on lower ones. In the non-stomata areas the epidermal cells arranged longitudinal lines, rectangular or nearly rectangular. The anticlinal walls of epidermal cells were mostly straight or sometimes undulate. Epidermal cells on areas with stomata were irregularly quadrilateral or polygonous. Sometimes cells were extruded flatly. Periclinal walls with cuticle were covered with dense crystalline or other massive appendages, without hairs. Stomatal apparatuses were oval, guard cells have polar layer structure. The type of stomatal apparatuses was bicyclic. Tests of various indices were significantly different.These indices can be used as indicators of varieties identification.⑶Results of leaves anatomy in Taxodium species and hybrids demonstrated that leaf was composed of upper epidermis, upper palisade tissue, spongy tissue, lower palisade tissue, and lower epidermis. Cross-section of leaves was determinated in the following shapes: elongately rod-like, irregular, inverted‘W’and’∞’shape. These shapes can be used as species and varieties identification. Taxodium trees were fit to wet and shaded habitat. The leaves were isobilateral anatomically. Tests of various indices were highly significant.⑷In this paper, cluster analysis was performed for Taxodium species and hybrids. An identification key was established for these species and hybrids.更多还原