杉木双系种子园无性系开花习性与异交率及其间的关系研究

Study on Flowering Habits and Out-crossing Rate and Their Relationships of Clones in Biclonal Seed Orchard for Cunminghamia Laceolata

基于对杉木双系种子园中成对无性系开花习性的多年观察及多年对杉木双系种子园的同工酶实验,运用EM算法估计各无性系的异交率大小,并使用DPS统计软件,详实地研究了异交率与开花习性诸多因素间的关系,其结果为:Y=0.877 7+0.104 4X1-0.615 8X2+0.354 4X3-0.061 8X4。上式中:X1为异系雄球花量,X3为异系开花同步性指数,它们对异交率的影响有正效应;而X2为系内开花同步性指数,X4为X3/X2之比,它们对异交率的影响有负效应。影响力的大小次序为:X2>X4>X3>X1。根据异交率与开花习性的关系研究,可以发现:今后新建杉木双系种子园时,挑选系内开花同步性小,而系间开花同步性大的双亲材料时,其后代异交率较高。

Based on observation of flowering habits about a pair of clones in biclonal seed orchard of Cunminghamia laceolata for many years,and allozyme experiment results for many years, the value and variability of out-crossing rate of different clones have been estimated by use of EM algorithm. At last, the relationships between out-crossing rate and flowering habits of clones have been studied by DPS software, the full and accurate results are as follows： （1） the linear model is Y=0.877 ＋0. 104 4 X1- 0. 615 8 X2＋ 0. 354 4 X3- 0. 061 8 X4 .Here： X1 is the amount of male cone of another clone; X2 is the synchronous index of female and male within clone; X3 is the synchronic index of female and male between different clones; X4 is the ratio of X3 to X2. （2） X1 and X3 have a positive effects on Y; X2 and X4 have a negative effects on Y. （3） In four variables, the order of their influence power on Y is X2〉X4〉 X3〉X1. The above results have been told us that from now on, biparental materials with the litter synchronic index within clone and the bigger synchronic index between different clones should be used in setting up biclonal seed orchard, their progenies have the higher out-crossing rate.