杂种马褂木杂种优势的遗传分析

GENETIC ANALYSIS OF HETEROSIS FOR HYBRID TULIP TREE

在叶培忠先生的鹅掌楸属种间杂交育种研究基础上按遗传设计与环境设计开展了扩大北美鹅掌楸遗传基础条件下的正反交以及前人从未做过的回交和F1 间杂交 ,并进行了杂种马褂木杂种优势的遗传分析。结果表明 :(1)正反交F1 、BC1 和F2 4种交配系统杂种的 1a生幼苗普遍存在显著正向生长杂种优势 ;幼苗生长性状在家系间存在极显著差异而在家系内具有很大变异性 ;回交家系表现特别优良 ,因而家系选择、单株选择以及BC1 和F2 利用潜力很大。 (2 )初步提出“光合优势假说”(Photosyntheticsuperiorityhypothesis)作为杂种马褂木和其它杂种树木杂种优势机理的理论解释。 (3)

Based on the Liriodendron interspecies hybridization study by professor Ye Peizhong,according to the satisfying and exact mating system and field design,the reciprocal cross with extensive genetic background of Liriodendron tulipifera Linn., the backcross and F 1 crossing which had never been made, and the genetic analysis of heterosis of the hybrid tulip tree were carried out.The results are as follows:(1)One year old hybrid seedlings of plus crossing,minus crossing,BC 1 and F 2 universally showed notable positive growth heterosis.Growth characters of the seedlings had extremely significant difference among families and expressed great variation among individuals of family.Growth performance of BC 1 families was particularly excellent.Thus family selection,individual selection and utilization of BC 1 and F 2 hybrids had tremendous potential.(2)The paper preliminarily put forth the photosynthetic superiority hypothesis regarding as the theoretical explanation of heterotic mechanism of the hybrid tulip tree and other forest-tree hybrids.(3)Some important genetic parameters were calculated simply.