杉木种子园子代性状相关性研究

为进一步了解杉木Cunninghamia lanceolata种子园子代遗传变异规律,提高杉木群体良种选育效率,以浙江省17个杉木种子园子代为研究材料,于1998-1999年,在临安市横畈林场采用10区组、3-4株小区的完全随机区组设计,营建2片子代试验林。自造林后第2年起,连续6 a调查测定树高、胸径、材积、冠幅和侧枝性状等,在数理统计分析的基础上,研究了种子园子代性状之间的表型相关、遗传相关以及年-年之间的生长相关和秩次相关等。结果表明,种子园子代树高、胸径和材积之间呈极紧密相关,相关系数rp和rg达到或近于1.0,通过胸径对材积进行间接选择,选准率100%。冠幅、盘间距与生长性状之间分别呈中度相关和轻度-中度相关,盘侧枝数与生长性状之间在遗传上没有相关关系,每米侧枝数则有负相关关系。不同年龄之间的年-年生长相关,随着年龄的增长而增大,其生长秩次变化在2-3年生时已逐渐稳定,5-6年生时基本稳定,rs高达0.96-0.99。在杉木种子园子代测定中,早期选择可从造林后第2年生长期结束时开始,但其选择率必须比第2次选择增加1倍。在此前提下,如以6年生选择作为第2次选择,选准率达100%,即在6年生选择时能入选的植株,在此情况下将无一漏选。表7参30

Correlations in progeny trials of Cunninghamia lanceolata

The objective is to find the regularity of hereditary variations in Cunninghamia lanceolata(Chinese fir)seed orchard and improve the stock breeding efficiency.Data were analyzed from two progeny trials of 17 Cunninghamia lanceolata seed orchards that were surveyed continuously over 6 years for phenotype and genetic correlations among growth traits,age,and rank correlation.Results indicatd a close correlation(P<0.05,rp and rg near or equal to 1.0)among growth traits of height,diameter,and stem volume.Crown width was significantly correlated to growth traits of height(P<0.01,rp=0.557 0,rg=0.699 7),diameter(P<0.01,rp=0.740 0,rg=0.881 2),and stem volum(P<0.01,rp=0.712 5,rg=0.847 7),whereas two growth rings was significantly correlated to growth traits of height(P<0.005,rs=0.461 0),diameter(P<0.05,rp=0.554 6),and stem volum(P<0.01,rp=0.537 5).Branch number per meter was negatively correlated to growth traits(P>0.01).The correlation coefficients of the growth traits between different years increased with age.The growth sequence tended to be stable when 2-3 years old,and became steady-state after 6 years.Within a progeny trial of C.lanceolata,the first selection from the orchard can begin after afforestation at the end of the second year of growth.The selection rate should be twice that of the second selection.With this selection criteria,the accuracy rate of the selection should be close to 100%.Also,when stem volume is selected indirectly by diameter,accuracy rate of the selection should be close to 100%.Ch,7 tab.30 ref.]