部分落叶松属植物核型研究

对落叶松属的兴安落叶松、长白落叶松、日本落叶松、华北落叶松、欧洲落叶松、美洲落叶松等6个种和日本落叶松×长白落叶松杂种进行了核型分析,所有材料的染色体数目均为2n=2x=24,2A核型。所有种的核型有着共同的构型,即二型核型。根据核型特征,可将以上各种分为三组:兴安落叶松、长白落叶松、日本落叶松为第一组,核型公式为2n=12m+10sm+2st;欧洲落叶松、美洲落叶松为第二组,核型公式为2n=12m+12sm;华北落叶松虽然具有与第二组相同的核型公式,但核型的对称性与其有一定差距,因此单独构成第三组。日本落叶松×长白落叶松杂种的核型数据和两个亲本的十分接近,表明这两个种杂交后染色体可能未发生明显的结构变异。作者认为长白落叶松和兴安落叶松的核型特征比较接近,从细胞学的角度作者支持长白落叶松作为兴安落叶松变种的观点。

The karyotype analysis of some Larix Mill.

This study analyzed the karyotypes of Larix gmelinii(Rupr.)Rupr.,L.olgensis Henry var.koreana Nakai,L.kaempfeeri(Lamb.)Carr.,L.principis-rupprechtii Mayr.,L.deciduas Mill.,L.laricina K.Koch and L.kaempfeeri×L.olgensis hybrids. All of them are 2n=2x=24 chromosomes. All the karyotypes are more or less symmetrical and fall into“2A”type. The karyotypes of all species we analyzed are bimodal karyotype,however,they can be divided into three groups based on their karyotype characters. The first group includes L.gmelinii,L.olgensis,and L.kaempfeeri and their common karyotype formula is 2n=12m+10sm+2st. The second group includes L.deciduas,and L.laricina of which the karyotype formula is 2n=12m+12sm. L.principis-rupprechtii itself constitute the third group for the discrepancy of chromosome symmetry although it has the same formula of the second group. The data of L.kaempfeeri×L.olgensis hybrids are very close to those of their parents and this shows that structural variety may not have arisen on chromosomal level after hybridization. The karyotypes of L.gmelinii and L.olgensis are similar and the authors approved L.olgensis as a variety of L.gmelinii.