赤皮青冈优树半同胞子代苗期遗传参数估算及选择

Estimation and Selection of Genetic Parameters at See dling Stage of Half-sib Progeny of Cyclobalanopsis gilva

于2016年,在福建省建瓯市东峰镇容锦轩苗圃,以3年生的12个赤皮青冈半同胞子代为对象,通过相关性分析、多重比较、方差分析及遗传参数估算,综合评价筛选优良家系。结果表明:赤皮青冈半同胞子代中苗高、地径、冠幅的变异系数均在20%以上,说明家系间的表型分化明显;各性状的家系遗传力均超过0.5,以苗高的家系遗传力最大,为0.839,说明对各性状进行遗传改良可以获得较大的遗传增益。擎天岩14号家系的苗高、地径、冠幅直径和叶长宽比均入选最大组,且苗高的遗传增益最大,达7.7%;擎天岩19号家系的地径、冠幅直径的遗传增益最高,分别达9.5%、3.8%。综合主成分分析、遗传增益和多重比较结果,筛选出4个优良家系,分别为擎天岩14号、擎天岩19号、擎天岩20号和擎天岩22号,以擎天岩19号家系为最优家系。入选家系的苗高、地径、冠幅直径的均值分别为135.054 cm、11.728 mm、49.042 cm,其现实增益均值分别为5.0%、1.7%、3.0%。研究结果可为赤皮青冈的遗传改良提供参考。

In this study,12 Cyclobalanopsis gilva half-sib progeny were selected as the object,and the excellent pedigrees were screened out by comprehensive evaluation through correlation analysis,multiple comparisons,variance analysis,and genetic parameter estimation.The results showed that the coefficient of variation of seedling height,ground diameter,and crown width in the half-sibling off spring of C.gilva were all above 20%,indicating that the phenotypic differentiation among families was obvious.The tree height,diameter at breast height,crown diameter,and leaf length-to-width ratio of the Q 14 family were all selected into a group.Estimated by heritability,the family heritability of each trait is more than 0.5,and the family heritability of tree height is the largest,which is 0.839,indicating that the family heritability of tree height is high,and the genetic improvement of each trait can obtain greater genetic gain.C.gilva half-sib progeny had the highest genetic gain for tree height in the Q 14 family,which was 7.7%;the Q 19 family had the highest genetic gain for ground diameter and crown diameter,which were 9.5%and 3.8%,respectively.Through the combination of principal component analysis,genetic gain,and multiple comparisons,4 excellent families were selected,namely Qingtianyan No.14,Qingtianyan No.19,Qingtianyan 20,and Qingtianyan No.22,among which the Q 19 family is the best pedigree.The average tree height,ground diameter,and crown diameter of the selected families were 135.054 cm,11.728 mm,and 49.042 cm,respectively,and their actual genetic gains were 5.0%,1.7%,and 3.0%,respectively.The results can provide reference for the genetic improvement of C.gilva.