不同产地木荷优树无性系生长和开花性状的分析

摘要

为比较不同产地木荷( Schima superba Gardn. et Champ.)优树无性系的生长性状(包括树高、胸径、冠幅和一级侧枝数)和开花性状(包括开花物候期和花朵数量)的遗传差异,采用方差分析、相关性分析和聚类分析方法,对来源于福建建瓯和连城、浙江庆元及龙泉和遂昌、江西上犹的22个木荷优树无性系的生长和开花性状进行了综合分析。结果表明：供试木荷无性系的树高、胸径、冠幅和一级侧枝数的的变异系数为19%~32%,始花时段、盛花时段、末花时段和花朵数量的变异系数为37%~73%,表明不同无性系生长和开花性状的变异较大。除木荷无性系一级侧枝数产地间的变异未达到显著水平外,其他生长和开花性状产地间和产地内的变异均达到显著或极显著水平。各生长和开花性状的无性系重复力为0.41~0.94,显示遗传控制程度中等偏强。无性系的树高、胸径和冠幅与花期的相关性均不显著,但与花朵数量呈显著或极显著正相关；来自较低纬度的无性系始花期最早,来自较高纬度或海拔的无性系始花期最晚。聚类分析结果显示：22个木荷无性系可聚为4个类型,类型1和类型4分别包含5个和7个无性系,这2类无性系的树高、胸径、冠幅和花朵数量总体上高于群体均值,生长表现优良、花朵数量较多,且类型4包含的无性系产地纬度较低、开花日期较早；类型2包含8个无性系,生长表现一般、花朵数量较少；类型3包含2个无性系,生长表现优良、花朵数量低于群体均值。研究结果显示：依据产地的纬度和海拔可初步判定木荷无性系的花期,可为木荷杂交育种亲本的选配和种子园建园过程中无性系的配置提供科学依据和理论基础。%In order to compare genetic difference of growth and flowering traits of Schima superba Gardn. et Champ. superior clones from different locations, taking methods of variance analysis, correlation analysis and cluster analysis, growth trait ( including height, DBH, crown width and primary lateral branch number) and flowering trait ( including flowering phenophase and flower number) of 22 superior clones of S. superba from Jian ’ ou and Liancheng of Fujian, Qingyuan, Longquan and Suichang of Zhejiang, Shangyou of Jiangxi were comprehensively analyzed. The results show that coefficient of variation of height, DBH, crown width and primary lateral branch number of S. superba clones tested are 19%-32%, that of early flowering stage, full flowering stage, late flowering stage and flower number are 37%-73%, which indicates that variations of growth and flowering traits of different clones are great. Except variation of primary lateral branch number of S. superba clones among different locations is not significant, variations of other growth and flowering traits among different locations and within location reach significant or extremely significant levels. Clone repeatability of all growth and flowering traits is 0. 41-0. 94, which shows medium to strong genetic control degree. Height, DBH and crown width of clones have no significant correlation with flowering period, but they have significantly or extremely significantly positive correlations with flower number. Early flowering date of clones from locations with lower latitude is the earliest, and that of clones from locations with higher latitude or altitude is the latest. The cluster analysis result shows that 22 clones of S. superba can be classified into 4 types. In which, type 1 and type 4 include 5 and 7 clones, respectively, and height, DBH, crown width and flower number of clones in the two types are totally higher than their average value of all clones, and clones of the two types grow well and have more flowers, and clones in type 4 are from lower latitude location and their flowering date is earlier; type 2 includes 8 clones, grows normal and has less flowers; type 3 includes 2 clones, grows well and its flower number is lower than average value of all clones. It is suggested that according to latitude and altitude of location, flowering period of S. superba clones can be determined preliminarily, and scientific and theoretical bases on cross breeding parental selection and clone configuration of seed garden construction of S. superba can be provided.