种间杂交和杂种优势利用是鹅掌楸Liriodendron spp.遗传改良的重要途径.报道了鹅掌楸不同交配类型和不同交配组合子代的生长表现及遗传稳定性.为杂交鹅掌楸品种选育提供参考依据.参试鹅掌楸交配组合39个,分属3种交配类型(种间杂交、种内杂交及回交),以鹅掌楸自由授粉子代为对照,在3个试验点进行子代测定.通过对各交配组合子代2年生苗进行苗高和地径比较分析.结果表明,就苗期生长量而言,鹅掌楸种间杂交、种内杂交及回交均显著高于对照.其中,种间杂交组合子代生长最好,种内杂交组合子代次之,回交组合优势较小.种间正反交组合间差异不显著.而同一交配类型的不同组合间差异达极显著水平(P＜0.01).表明在鹅掌楸杂种优势利用时.应重视杂交亲本的选择.同时,利用Eberhart和Russell模型评价了各杂交组合的生长适应性与遗传稳定性,并初选出生长快、适应性强、综合性状较优的组合J×L,而组合BKl×H和Z×WYSl生长较快,但稳定性较差.表5参16%In order to select the best mating combinations from three mating systems (inter-species crossing,intra-species crossing, and backcross), interspecific hybridization and heterosis (two preferred genetic improvement methods) were utilized in progeny testing of all 39 mating combinations in Liriodendron (L.chinense, L.tulipifera and L.chinese × tulipifera) to determine variation and genetic stability of growth, in terms of height and ground diameter, for two-year-old seedlings.Progeny testing at the seedling stage was implemented simultaneously in three sites, with open-pollinated offspring of Liriodendron chinense taken as the control.Also, the Eberhart and Russell analysis was used with a regression of genetic stability for the 39 combinations.Results showed that seedling growth for all 39 mating combinations was significantly greater (P＜0.01) than the control.Seedling growth from high to low was: inter-specific mating ＞ intra-specific mating ＞ backcross.No significant differences were found between progenies of reciprocal crosses with the same parents, whereas significant differences (P＜0.01) existed among combinations within the same mating types.Furthermore, the Eberhart and Russell analysis showed that mating combination J × L had good potential due to fast growth and high genetic stability, whereas BK1 × H and Z × WYS1 had fast growth but low genetic stability.Thus, to utilize the hybrid vigor within Liriodendron, selection of mating parents should be a priority consideration.
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