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作 者 ：饶龙兵1,杨汉波1,2,郭洪英3,段红平2*,陈益泰1

期 刊 ：西北植物学报 2013年 7期 页码：1333~1338

关键词：桤木属；染色体；核型分析；

Keywords:Alnus, chromosome, karyotypes,

摘 要 ：利用改良去壁低渗法对分布于欧美地区的桦木科（Betulaceae）桤木属（Alnus Mill.）7种植物进行染色体数目与核型分析。结果显示：所有材料染色体形态比较一致,多为由中部（m）及近中部（sm）着丝点染色体组成。意大利桤木(A.cordata)为六倍体,体细胞染色体数为2n=6x=42,核型公式为2n=6x=42=36m+6sm;绿桤木(A.viridis)为八倍体,体细胞染色体数为2n=8x=56,核型公式为2n=8x=56=46m+10sm(SAT);薄叶桤木(A.tenuifolia)、灰桤木(A.incana)、欧洲桤木(A.glutinosa)、裂叶桤木(A.sinuata)和红桤木(A.rubra)均为四倍体,体细胞染色体数均为2n=4x=28,其核型公式分别为2n=4x=28=16m(1SAT)+12sm、2n=4x=28=22m+6sm、2n=4x=28=24m+4sm、2n=4x=28=24m+4sm、2n=4x=28=26m+2sm。其中红桤木(A.rubra)的核型属于1B型,其余均为2B型。

Abstract:The chromosome number and karyotypes of seven species of Alnus in European and American areas were studied by shedding cell wall and dialysis methods.The results showed that the karyotypes among them were not distinct and most chromosomes were metacentric or submetacentric.The chromosome number of A.cordata (hexaploid) was 2n=6x=42,the karyotype formula was 2n=6x=42=36m+6sm;2n=8x=56 and 2n=8x=56=46m+10sm(SAT) for A.viridis (octoploid);The chromosome number in somatocyte of A.tenuifolia,A.incana,A.glutinosa,A.sinuata and A.rubra all were 2n=4x=28,were tetraploid.The karyotype formula were 2n=4x=28=16m(SAT)+12sm,2n=4x=28=22m+6sm,2n=4x=28=24m+4sm,2n=4x=28=24+4sm,2n=4x=28=26m+2sm.A.rubra belonging to “1B” of Stebbins,the rest six species belong to “2B” of Stebbins.

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