乐昌含笑种源不同林龄生长变异及早期选择  

Growth variation of Michelia chapensis provenance in different ages and its early selection

作　　者：韦如萍[1] 晏姝[1] 郑会全[1] 王润辉[1] 胡德活[1] WEI Ruping;YAN Shu;ZHENG Huiquan;WANG Runhui;HU Dehuo(Guangdong Provincial Key Laboratory of Silviculture,Protection and Utilization,Guangdong Academy of Forestry,Guangzhou 510520,Guangdong,China)

机构地区：[1]广东省林业科学研究院广东省森林培育与保护利用重点实验室,广东广州510520

出　　处：《浙江农林大学学报》2023年第2期365-373,共9页Journal of Zhejiang A&F University

基　　金：广东省林业科技创新项目(2022KJCX010)。

摘　　要：【目的】研究乐昌含笑Michelia chapensis主要生长性状的遗传变异规律及幼林期与近成熟林期主要性状的相关性,探析乐昌含笑种源早期选择的适宜林龄。【方法】利用种植于广东省韶关市国有曲江林场和九曲水林场的乐昌含笑种源试验林多个年度的观测数据,采用方差分析、遗传参数估算、相关分析及聚类分析等方法,对胸径、树高及材积生长性状在林龄为3、6、11、14 a的遗传变异模式进行分析,并确定早期选择的适宜林龄范围。【结果】种源试验林的保存率在林龄为11~14 a有较明显下降;各林龄的树高、胸径、单株材积在种源间存在极显著差异(P<0.01);种源效应对生长性状的影响随林龄的增大而逐渐增强或趋于平稳;各林龄的树高、胸径、单株材积的种源遗传力为0.69~0.90;林龄为3、6、11 a时的树高、胸径、单株材积分别与林龄14 a的单株材积间存在极显著(P<0.01)的表型相关和遗传相关;综合指标法和单指标法对参试种源分类评价表明:所得丰产型Ⅰ类种源的分类结果较一致,但单指标法更简便;以林龄为14 a时入选的丰产型Ⅰ类种源为参考时,单指标法的早期选择风险更低,在林龄为3、6 a时开展早期选择,2片试验林的选对率为83%~100%,漏选率均为0。【结论】乐昌含笑树高、胸径、单株材积生长性状在不同种源间存在丰富变异,种源效应对3个生长性状有明显且较稳定的影响,树高、胸径、单株材积的种源遗传力属中等偏高水平。以丰产型种源为选择目标,在林龄为3~6 a时开展单株材积的早期选择是可行的。[Objective]This study,with an investigation of the genetic variation of Michelia chapensis and the correlation between the main growth traits of juvenile trees and those of the adult trees,is aimed to determine the suitable age for the early selection of M.chapensis provenances.[Method]First,two testing forests of M.chapensis provenances with an age range of 3 to 14 planted in Qujiang forest farm and Jiuqushui forest farm,Shaoguan,Guangdong Province were selected for measuring growth traits.Then,an analysis was conducted of the genetic variation of growth traits at different ages with the employment of variance analysis,genetic parameter estimation,correlation analysis and cluster analysis before the suitable age of early selection was determined.[Result]The preservation rate of testing forest had significantly decreased in 11−14 years with significant differences(P<0.01)in tree height,diameter at breast height(DBH)and individual volume among tested provenances at different ages.The provenance effect had a significant impact on growth traits,which was gradually enhanced or tended to stabilize with the increase of age.The range of the provenance heritability for tree height,DBH and individual volume at different forest ages were 0.69−0.90 displaying significant phenotypic and genetic correlations between the early tree height,early DBH or early individual volume and the individual volume at the age of 14.As was shown in the classification and evaluation of provenances using comprehensive index and single index methods,the consistency of high-yield typeⅠprovenances obtained by the two evaluation methods was very high,but the single index method was relatively easier to operate.Taking the high-yield typeⅠprovenances selected in 14 years old as a reference,the early selection risk of single index method was lower than that of comprehensive index method.Using the single index method to carry out early selection at the age of 3 and 6 years,the correct selection rate of the two experimental forests was 83%−100

关 键 词：乐昌含笑 种源 遗传变异 早晚相关 早期选择 

分 类 号：S722.3[农业科学—林木遗传育种]