木兰科13个分类群和12个杂交组合的染色体数目

Chromosome numbers of 13 taxa and 12 crossing combinations in Magnoliaceae

对木兰科Magnoliaceae13个分类群的染色体进行了计数,其中落叶木莲Manglietiadecidua、香港木兰Magnoliachampionii、馨香玉兰Magnoliaodoratissima、香木兰Magnoliaguangnanensis等12个种的染色体数目为首次报道。同时对木兰科属内属间的12个人工杂交组合的后代进行了染色体鉴定,其中,二乔玉兰红元宝Magnolia×soulangeana“Hongyuanbao”(♀,2n=4x=76)与云南含笑Micheliayunnanensis(♂,2n=2x=38)、红元宝与金叶含笑Micheliafoveolata(♂,2n=2x=38)杂交后代的染色体为2n=3x=57,为其亲本染色体半数之和,证明这两个远缘杂交后代为真实杂种。

Chromosome numbers of 13 taxa and 12 crossing combinations in the Magnoliaceae are reported. The counts of 12 taxa are reported for the first time. The intergeneric crossing combination between Magnolia × soulangeana “Hongyuanbao” （♀）, a tetraploid with 2n=4x=76, and Michelia yunnanensis （♂）, a diploid with 2n=2x=38, had the number of 2n=3x=57, a half of the total chromosome number of its parents. Similarly, the intergeneric crossing combination between Magnolia× soulangeana “Hongyuanbao” （♀） and Micheliafoveolata （♂）, a diploid with 2n=2x=38, also had the number of 2n=3x=57. These indicate that the offspring of the two crossing combinations are true hybrids.