【作者】 周玉珍；

【导师】 张启翔；

【作者基本信息】 北京林业大学 ， 园林植物与观赏园艺， 2006， 博士

【摘要】 墨西哥落羽杉(Taxodium mucronatum Tenore)是属杉科(Taxodiaceae),落羽杉属(Taxodium Rich.)植物,是丘陵山区、平原水网地区优良的用材、园林绿化及防护林树种。对于墨西哥落羽杉优良无性系的选育和规模化种苗生产,国内外研究尚属空白。本文在对墨西哥落羽杉实生苗的生长量、树冠类型和叶色等方面研究的基础上,开展墨西哥落羽杉速生型、叶色金黄型、不同树冠类型优良无性系的选择工作,并对部分无性系的耐盐性、光合特性等进行测定,期望从中选育出能满足园林观赏、用材生产和防护林营造等不同需要的优良无性系。论文主要研究结果:2000年吴江市苗圃有限公司从墨西哥东部引进墨西哥落羽杉种子,2001年获得10万株实生苗。2003年7月采用绝对标准法对墨西哥落羽杉群体进行优良单株的选择,初选出991株优良单株。其中,以生长量为选育目标的优良单株837株,地经和株高的选择差及选择强度分别为0.84cm、56.78cm,和1.5、1.89;以园林观赏为育种目标的优良单株92株;叶色金黄的优良单株62株。优良单株的嫩枝扦插试验结果表明墨西哥落羽杉优良单株扦插成活率和穴盘苗移植成活率总体较高,分别达86%和95% ,同时,扦插成活率和移植成活率在无性系间差异显著。以897个墨西哥落羽杉优良单株无性系(包括速生型、园林观赏株型和叶色金黄型)为试验材料,开展无性系苗期比较试验。方差分析结果表明,苗高、地径无性系间差异均达到极显著水平,表明对生长性状进行无性系选择是可行的。苗高、地径的广义遗传力分别为0.2673和0.2029。通过构建包括地径、苗高两生长性状的选择指数,以10%的入选率,复选出墨西哥落羽杉速生型优良无性系77个,园林观赏型优良无性系8个;叶色金黄型优良无性系5个。利用随机多态扩增DNA(RAPD)分子标记对53个墨西哥落羽杉无性系的研究表明:31个随机引物共扩增出了241条带,其中118条谱带在无性系间呈现多态性,多态位点占48.96% ,用POPGENE软件对无性系进行遗传分析,结果表明无性系间的遗传距离最小为0.2709,最大为0.5366,且无性系间的遗传差异相对较大,UPGMA分析将53个优良无性系分为两大类。因此,可借助构建的RAPD指纹图谱对优良无性系区分和鉴定。以墨西哥落羽杉无性系扦插苗为材料,测定了其耐盐能力及其无性系之间的差更多还原

【Abstract】 Taxodium mucronatum, one species of the genus Taxodium Rich in the family of Taxodiaceae, was widely planted in mountainous area and wetland on the purpose of both protection-forest and timber production forest. However, nothing has been reported yet on its breeding, propagation till now and selection of superior clones and scale seedling production of Taxodium mucronatum. Based on the research on the traits of growth, crown types, leaf color, a group of clones of Taxodium mucronatum for different breeding goals as fast growing, golden leaf and nice crown were selected. Besides this, the salt tolerance and photosynthesis characteristics of some clones were also evaluated. The final goal of this study is to select several superior clones of Taxodium mucronatum with virtues in fast-growing, nice crown, golden leaf and high salt-tolerance. The main results of this dissertation are as follows:100 kg seeds of Taxodium mucronatum were introduced from Eastern Mexico by Wujiang City nursery Co., Ltd in 2000, and a population of 100000 seedlings was established at Wujiang City nursery the next year. In 2003, 991 plus trees had been selected from it based on the individual investigation of growth and crown characteristics, among which, 837 plus trees were selected for their merit of fast growing, 92 trees for their unique crown, and 62 for their golden leaves. The selection differential (S) of diameter at base (D) and height (H) were 0.84cm and 56.78cm respectively, and the selection intensity (I) of D and H were 1.5 and 1.89 respectively. On the whole, a conclusion could be drawn that Taxodium mucronatum could be easily vegetative propogation due to their high survival percentage (86% for cuttings and 95% for transplants), whereas a significant variation of survival ratio among plus trees was found.897 clones originated from plus trees of Taxodium mucronatum were tested at Wujiang nursery in March, 2004. The ground diameter (D) and height (H) of each ramet were investigated in March, 2005. A significant variation of growth was found among更多还原