【作者】 姚小华；

【导师】 谢碧霞； 韩宁林；

【作者基本信息】 中南林学院 ， 森林培育， 2002， 博士

【摘要】 针对我国亚热带地区常绿阔叶林树种遗传改良基础薄弱、主要阔叶树种良种化程度低、工程造林常绿阔叶树良种缺乏的现状，选择樟树这一种亚热带地区优势的多用途树种为对象开展研究。目的是通过研究，阐明樟树的生长、适应性性状等方面的地理变异规律，为樟树的良种选育提供理论依据，同时为樟树的长期遗传改良打下基础工作并为当前生产提供初级良种材料。本研究课题来源于“九五”科技攻关“长江中下游防护林植物材料选育与培育技术研究”专题(96-007-02-16)中的《樟树良种选育与培育技术研究》子专题、浙江省科委项目“绿化用樟树优良种源和物种筛选(991102297)和湖北省科委“湖北省南部丘陵平原区樟树优良种源选择”(99P1010)项目。本研究内容主要有樟树种源地理变异规律的研究和优良种源选择以及种源区的划分。通过对我国樟树自然分布区15个省区47个产地采集的樟树种子进行取样观测分析表明，樟树种子形态存在显著的产地差异，种子的大小存在明显的经向变异，种形指数(长宽比)与纬度呈显著的负相关。种形指数与苗期生长有密切的关系。根据樟树种子的大小、形状、百粒重等7个性状的产地平均数，采用欧氏距离类平均法进行聚类分析，初步将樟树种子性状自然分布区划分为6个类群。苗期种源试验研究表明，苗木高、地径、分枝高和冻害在种源间有显著差异；苗期生物量种源间差异显著；包括苗高和地径在内的各性状之间存在着显著的表型和遗传相关；与苗期单株生物量相关最为紧密的性状是地径(r_P=O.847,r_G=0.802)。通过无约束指数选择法，评定了各种源的综合表现，并选出广东连州、江西井岗山、福建建瓯、浙江庆元、福建上杭5个苗期表现优良的种源。种源的苗期生长和冻害与地理纬度间和许多温度指标间有显著的相关关系，性状与纬向的相关程度比经向大得多，冻害是限制较大地理区种子调运的关键因素。樟树苗期种源/家系二水平试验研究表明，樟树的遗传变异存在于种源和家系二个层次。樟树苗高、枝下高、冻害性状在种源层次的变异远大于家系层次的变异，地径则相反。方差分析表明，樟树苗期种源间在苗高、地径、枝下高、冻害性状上有极显著差异；家系之间在苗高、地径、冻害性状上有极显著差异，在枝下高性状上无显著差异。种源内大多数家系间在各性状的差异达不到显著水平。在苗高、地径、枝下高、冻害各性状，高于富阳种源(ck)的家系分别有125、95、88、108个，低于富阳种源(ck)的分别有56、86、93、73个。苗高与种源纬度负显著相关，与年均温、1月均温、绝对低温显著相关；冻害与纬度负极显著相关，与年均温、1月均温，绝对低温显著相关；枝下高与纬度显著相关，与年均温、1月均温、绝对低温负显著相关；苗高与冻害极显著相关，与地径显著相关。二水平试验中关于性状与地理相关的一些结论与种源试验的结果相似。同样樟树遂川试验点的种源/家系二水平物候试验研究表明，樟树的苗期萌芽率遗传变异存在于种源和家系二个层次。樟树早期萌芽百分率、中期萌芽百分率、晚期萌芽百分率在种源层次的变异远大于家系层次的变异。方差分析表明，樟树苗期种源间在早期萌芽百分率、中期萌芽百分率上有极显著差异，晚期萌芽百分率性状有显著差异；家系之间在早期萌芽百分率性状上有极显著差异。种源内大多数家系间在苗期萌芽率上达不到显著水平。早期萌芽百分率、中期萌芽百分率、晚期萌芽百分率各性状，高于遂川种源的家系分别有84、83、104个，低于遂川种源的分别有107、108、87个。早期萌芽百分率、中期萌芽百分率、晚期萌芽百分率与地理纬度均呈负相关，其中早期萌芽百分率、中期萌芽百分率与地理纬度呈负极显著相关；早期萌芽百分率、中期萌芽百分率与年均温、l月均温和绝对低温极显著相关，早期萌芽百分率与干季月数显著相关。早期萌芽百分率、中期萌芽百分率、晚期萌芽百分率之间呈极显著相关。对试验林研究表明，樟树叶色在种源间存在极显著差异，这表明在不同种源间进行叶色性状的选择具有较大的潜力。在叶色值小的种源上选择红色或紫红色单株有较大的可能性，数值越小的种源这种可能性就越大。相反在叶色值大的种源中进行偏绿色叶色的单株选择具有较大的可能性，数值越大偏绿单株比例越大，叶色值与种源所在地湿度有一定的关系。开花性状在种源间存在极显著差异，南京种源极显著高于樟树平均值和对照，铜仁、黄山、埔析显著高于樟树平均值和对照。开花率与种源纬度呈极显著相关而与多个温度指标呈负显著或极显著相关，开花率也和年雨量呈负极显著相关、与干燥指数呈显著相关。从叶色值和开花性状上，猴樟和黄樟均不同程度高于樟树对照种源和所有种源的平均值。试验林造林后4个试验点各选出优良种源6个。研究表明种源与地点交互作用达到极显著水平；在初步选出的优良种源中，生长优良且具较高稳定性的种源有福建邵武、广西全州、贵州铜仁、道真、湖南郴州、湖北埔沂。幼年期樟树树高、胸径生长与经度呈极显著负相关，冻害与纬度呈极显著负相关。樟树幼年期种源／家系二水平试验表明，余杭试验点和遂川试验点不同性状在家系间差异显著，种源层次的?更多还原

【Abstract】 Wide range provenance and provenance /family trails of Cinnamomum comphora (L.)Presl were carried out at 4 sites located at the middle and lower reaches of Yangtze River with over 50 provenances and 180 families at different tests. At first ,the traits of seeds were analyzed with the clustering analysis and the provenances classified. Provenance and family variation of growth, adaptation, and genetic satability were analyzed at the stage of seedling and plantation. Genetic diversity and relationship were discussed based on the data of PCR-RAPD analysis. At last, the provenances were classified and the best provenances, families and trees were selected also. The major results were as follows.1. The seed characters of C. comphora, such as length, width, high, weight , 100 seeds weight were investigated for 47 locations. The results show that seed characters and seedling survival percent in the field having significant variation among locations. According to the correlation analysis for the seed traits with the stands environment and seedling growth traits, the close relation were found between seed size and longtitude, between seed shade and height of seedling. According to The cluster analysis for the 7 seed trait means of locations, the natural range of C. comphora could be divided into 6 districts.2. The provenance test at seedling stage was carried out at the nursery of Changle Forestry Farm in Yuhan city, Zhejiang province in 1997 with the 50 provenance seeds collected from the distribution area of C. comphora in 1996. Seedling Biomass and relative traits on the test were observed and the relationship among traits was analyzed with variance analysis, relationship analysis, progressive regression analysis and comprehensive index selection. The results show that there is extreme significant difference on the seedling biomass among provenances and there is extreme significant relationship among 9 traits including seedling height and seedling ground diameter, in which the ground diameter is a leading factor related to the seedling total biomass. Also, five best superior provenances are selected with the comprehensive index selection.3. Growth variance and character analysis of C. camphor a seedling from different provenances: The research is carried out based on the observation data of 8 traits of 10 C. camphora provenances, represented total distribution area of the tree , from test with 60 provenances by the methods of variance analysis, relationship analysis and progressive122regression analysis. The results show that there is significant difference for different traits among provenances; there is extreme significant relationship among 7 traits including seedling growth and ground diameter and the latter is leading factor which has tightest relationship with total biomass at seedling stage.4. The research on provenance /family test shows that there is genetic variation on provenance level and family level. The genetic variation of seedling height, branching height, freeze injury value is much greater on provenance level than that on family level, and the contrary for ground diameter trait on family level. The variance analysis shows there is extreme significant difference in seedling height, ground diameter, branching height, freeze injury value among provenances; there is significant difference in seedling height, ground diameter and freeze injury value and no significant difference in branching height among families, and there is no significant difference for many traits among families within provenance. There are 128, 95, 88, 108 families with higher value and 56, 86, 93, 73 families with lower value compared to Fuyang provenance in seedling height, ground diameter, branching height, freeze injury. Seedling height has significant negative relationship with latitude and significant relationship with annual mean temperature, Jan. mean temperature and extreme lowest temperature; freeze injury value has extreme significant negative relationship with l更多还原