Variation of annual growth traits and early selection of different provenances/families of Toona ciliata var.pubescens
[Objective]This study aims to explore the differences in growth traits of young forests of Toona ciliata var.pubescens provenances and families.The provenances/families with excellent early growth traits were screened,and their geographical variation rules were revealed,so as to promote the genetic improvement of Toona ciliata var.pubescens.[Method]Taking 11 families of 5 provenances of T.ciliata var.pubescens as the research objects,the growth traits including tree height and diameter at breast height were investigated.The genetic variation and correlation analysis of growth traits of different provenances/families were analyzed,and the genetic gain was used to select excellent provenances/families.[Result]There were significant differences in early growth traits among provenances and families(P<0.01).No.14(Yifeng,Jiangxi)had the best performance and fastest growth in tree height,diameter at breast height and volume,while No.1(Jingxian,Anhui)and No.4(Jingxian,Anhui)grew relatively slowly.The annual growth of No.2,No.13,No.14 and No.15 was higher.The variation coefficients of tree height,diameter at breast height and volume were 25.39%-32.74%,31.94%-36.55%and 80.81%-91.21%,respectively,the variation coefficients of 5-year-old T.ciliata var.pubescens forest were ranking as follows:volume>diameter at breast height>tree height,and their heritability were 0.586-0.894,0.749-0.852 and 0.643-0.780,respectively.The results of correlation analysis showed that except for the correlation between growth traits and frost-free period,the correlation between 5-year old branch height and longitude and annual average precipitation was not significant,the correlation between each growth trait reached extremely significant level(P<0.01).Each growth trait showed extremely significant negative correlation with longitude and latitude(P<0.01),and extremely significant positive correlation with annual average temperature and annual average precipitation(P<0.01).Comprehensive evaluation was conducted according to the results of principal component analysis.Three excellent families(No.12,No.13 and No.14)were preliminarily selected.The genetic gains of tree height,diameter at breast height and volume of No.14 family were 14.94%,16.59%and 38.20%,respectively.[Conclusion]The growth traits of T.ciliata var.pubescens has rich genetic variation among provenances and families,and shows obvious'two-way gradient'in geography.The preliminary screening of No.14(uanshan)family not only grows well,but also has a high genetic gain.It could be used as the preferred family for popularization and application,and could provide the basis for the breeding of Toona ciliata var.pubescens.
Toona ciliata var.pubescensgrowth traitsgenetic variationprovenance/family selection
万方数据
维普
