摘要
研究了木兰科 1个属内种间杂交组合红花山玉兰 (Magnoliadelavayi) (♀ )×广玉兰(M grandiflora) (♂ )和 1个属间杂交组合红花山玉兰 (♀ )×乐东拟单性木兰 (Parakmerialotungensis) (♂ )的亲本及F1代的染色体数目和形态。结果表明 ,前者的杂交后代染色体数目为 76条 ,正好是二倍体红花山玉兰 (2n =2x =38)和六倍体广玉兰 (2n =6x =114 )的半数之和 ,且在F1代的分裂中期染色体具大小两种类型 ,可以明显看出来自红花山玉兰的染色体较大 ,而来自广玉兰的染色体较短小 ,这证明该F1为两者的杂交种 ;而后者的杂交后代染色体数仅为 38条 ,而不是二倍体山玉兰和六倍体乐东拟单性木兰 (2n =6x =114 )的半数之和 ,且所有染色体形态都与红花山玉兰相同这证明该F1代不是真正的杂交种 ,可能是无融合生殖的结果。本研究结果表明细胞学方法是木兰科植物杂交育种中早期检测的有效方法之一。
The chromosome number and size of five taxa, Magnolia delavayi, Magnolia grandiflora , Parakmeria lotungensis ,a interspecific hybridized combination between Magnolia delavayi (♀) and M grandiflora (♂) and a intergeneric hybridized combination between Magnolia delavayi (♀) and Parakmeria lotungensis (♂), were studied in this paper. Magnolia delavayi is a diploid species with a chromosome number of 2n=2x=38, Magnolia grandiflora and Parakmeria lotungensis are hexaploid species both with chromosome number of 2n=6x=114. The interspecific hybridized combination is tetrploid taxon with a chromosome number of 2n=4x=76, which was a half of the total chromosome number of its two parents. Of which, 19 chromosomes from M delavayi are larger, and 57 chromosomes from M grandiflora are smaller. So, the hybrid was confirmed to be crossbreeding filial generation of M delavayi and M grandiflora . The intergeneric hybridized combination is a diploid taxon with a chromosome number of 2n=2x=38, which is the same to that of female parent, M delavayi ,in number and size. So, the hybridized combination is not a real hybrid, and the filial generation may be resulted from apomixes. The study showed that cytological method is one of efficient measures applied to early identification in crossbreeding of Magnoliaceae.
出处
《云南植物研究》
CSCD
北大核心
2002年第5期659-662,共4页
Acta Botanica Yunnanica
基金
云南省中青年学术与技术带头人后备人才培养资助项目
