粤东地区西南桦优良无性系多性状综合选择

摘要

对广东省惠州市20个西南桦无性系5年生时的生长和形质性状进行测定和分析,应用简单选择指数法进行优良无性系筛选,旨在选出适宜粤东地区的优良无性系,为该地区西南桦推广应用提供科学依据.结果表明:除树高和分枝外,各性状在无性系之间存在显著差异(P＜0.05);11个无性系的单株材积超过总体均值,其中表现最好的为18号无性系,其单株材积(0.063±0.009m3)比总体均值高76.54％.各性状的无性系重复力为21.63％～74.27％,以冠幅的重复力为最高,分枝的最小.按照20％的入选率,最终选出18、4、8和7号4个优良无性系,其单株材积增益达到31.53％.%A clonal test,with 20 Betula alnoides clones involved,was conducted at Huizhou city,Guangdong province in terms of growth performance,stem form,branching and crown form when five years old,and simple index selection method was applied to evaluate these clones comprehensively,so as to screen out superior clones and promote spread and utilization of this species in eastern Guangdong.The results showed that there were significant differences among clones at the level of 0.05 in all sorts of traits except tree height and branching.Of 20 B.alnoides clones,11 clones showed higher individual volume than the mean value of all clones,and Clone 18 was of the best performance with its individual volume being 0.063± 0.009 m3,76.54％higher than the overall mean.The clonal repeatability of all traits ranged from 21.63％ for branching to 74.27％ for crown diameter.Under 20％of selection rate,four superior clones,coded as 18,8,4 and 7 were selected with gain of individual volume reaching 31.53％.