关键词: 鹅掌楸属, RAPD, 遗传距离, 杂种识别, 亲本选配

Abstract:

According to the genetic difference detected by means of RAPD markers, the methods of distinguish among 2 Liriodendron species and their interspecific hybrid were discussed, and the relationship between genetic distances of parents and their hybrids performance were analysed. Of the total 136 bands amplified with 25 10-mer primers, 3 presented in all 5 L.chinense sample trees, but absented in all 5 L.tulipifera sample trees. On the contrary, 8 presented in all 5 L.tulipifera sample trees, but absented in all 5 L.chinense sample trees. The 11 fragments could be detected in all the 6 hybrids sample trees. It was considered that 11 fragments could be used as markers in the identification. The range of genetic distance among 5 L.chinense sample trees, among the sample trees between L.chinense and L.tulipifera and between L.chinense and the hybrid were not overlapped. Therefore, the genetic distance between an unidentified tree and a L.chinense tree could also be used in the hybrid identification. The 16 sample trees were grouped correctly. So, the UPGMA (unweighted pair group methods of arithmetic (average))cluster analysis method was useful in the (hybrid) species identification. The mean height and basae diameter increment of families after the first growing season showed a significant guadratic cure correlation with genetic distances of parents. Therefore, the genetic distance had high potential for the choice of parents and the heterosis prediction in cross breeding of Liriodendron.

Key words: Liriodendron, RAPD, Genetic distance, Hybrid identification, Parents choice