中文摘要：

以鹅掌楸属树种5个自交组合子代为材料,以4个种内杂交子代及8个种间杂交子代为参照,以存活率、生长量等表型性状为评价指标,结合SSR分子标记信息分析鹅掌楸属树种自交衰退程度,并试图从SSR分子标记角度探究其遗传机制。结果表明,鹅掌楸属树种自交衰退明显。与种内异交及种间杂交子代相比,自交子代胸径、树高及存活率的衰退程度δ分别为：0.46,0.45;0.32,0.35;0.25,0.30。SSR检测结果显示,不同交配类型子代的纯合子比率由高到低趋势为：自交、种内交配、种间交配。同时,初步筛选出2个可能与鹅掌楸属隐性致死基因相关联的SSR位点。

英文摘要：

The existing Liriodendron has a small population size,and hence easily occurs selfing depression. In this study,we analyzed selfing depression of Liriodendron by taking 5 selfing progenies as experimental populations,4 intraspecies progenies and 8 inter-species progenies as reference populations. The phenotypic traits such as survival rate and growth were used as evaluation index,combined with SSR molecular marker,to analyze the extent of selfing depression in Liriodendron. The aim of this study is to explore the underlying mechanism of selfing depression. The results showed that the selfing depression in Liriodendron chinense was obvious. By taking progenies of intra-species cross and inter-species cross as references,the degree of depression（ δ value） of selfing progenies for DBH,height and survival rate were 0. 46, 0. 45; 0. 32,0. 35; and 0. 25,0. 30 respectively. SSR test results showed that the homozygous progeny rate derived from different mating types of selfing,intra-species,inter-species was from high to low trend. Moreover,we also detected 2 candidate SSR loci that might relate to recessive lethal gene in Liriodendron.