白榆( Ulmus pumita Linn.) 优树半同胞子代测定林生长量遗传参数方差分析和亲子回归分析结果表明, 树高遗传力约为胸径的 3 倍, 遗传增益约为胸径的 2 倍;半同胞子代树高的遗传增益高达 11.26%或 11.97 %, 胸径的遗传增益为5.20%或 7.30 %。 经无性系各性状与生长量通径分析得出, 直接影响树高和胸径生长量的因子以绝对值大小排列顺序为树皮>侧枝>顶端优势>树冠>枝角;促进树高和胸径生长的主要因子及相对性状为粗树皮。 经亲代各性状与生长量通径分析得出, 各因子按直接影响树高和胸径生长量的因子以绝对值大小排列顺序为:材积>树皮>顶端优势>枝角>侧枝;促进亲代各性状对子代树高生长的主要因子及相对性状为大材积;促进子代胸径的主要因子及相对性状为浓密树冠。
 

Result was obtained from calculating genetic parameter variance analysis and filial regression of plus tree of Ulmus pumita Linn .cloning halfsib progeny measuration forestry growth increment : tree height heritability was about 3 times of breast height diameter, and the heredity benefit was about 2 times of breast height diamater, and heredity gain of cloning halfsib progeny′height was 11 .26 %or 11 .97 %, heredity gain of breast height diameter was 5 .20 %or 7 .30 %.By path analysis of relation between cloning′every character and growth increment, such result was obtained :the absolute value size of factor directly affecting tree height and normal diameter was :bark >lateral branch >apical dominance >tree crown >branch angle ;the primary gene and relative character accelerating tree height was thick bark .By path analysis the relation between parental generation′every character and growth increment, such result was obtained :the absolute value size of factor directly affecting tree height and normal diameter growth increment :timber volume >bark >apical dominance >branch angle>lateral branch ;the primary gene accelerating parental generation′every character to filial generation height was great timber;the primary gene accelerating filial generation mormal diameter was dense crown .