青藏高原东缘高寒草甸风毛菊属4个优势种的核型研究

On karyotypes of four species of Saussurea DC.in the east of Qinghai-Tibet Plateau

对青藏高原东缘高寒草甸风毛菊属的球花雪莲(S aussurea g lobosa Chen.)、钝苞雪莲(S.n ig rescensM ax im.)、羽裂风毛菊(S.p inna tid enta ta L ipsch.)和林生风毛菊(S.sy lva tica M ax im)4个优势种植物的染色体数目和核型进行了研究。结果表明,球花雪莲的核型公式为2n=2x=32=14m+18sm,属2B型,核型不对称系数为64.8%;钝苞雪莲的核型公式为2n=2x=32=10m+22sm,属2B型,核型不对称系数为66.1%;羽裂风毛菊核型公式为2n=2x=28=24m+4sm,属2B型,核型不对称系数为58.6%;林生风毛菊的核型公式为2n=2x=34=10m+24sm,属3B型,核型不对称系数为64.6%。钝苞雪莲较其他3种风毛菊属植物进化。

The numbers and the karyotypes of four dominant species of Saussurea DC. were analysed. The results as follows .S. globosa Chen. 2n = 2x= 32 = 14m ＋ 18sm, karyotype belongs to 2B type, the coefficient of karyotype asymmetry is 64.8 % ;S. nigrescens Maxim. 2n = 2x = 32 = 10m ＋ 22sm,karyotype belongs to 2B type, the coefficient of karyotype asymmetry is 66. 1% ; S. pinnatidentata Lipsch. 2n = 2x = 28 = 24m＋4sm,karyotype belongs to 2B type,the coefficient of karyotype asymmetry is 58. 6%;S. sylvatica Maxim. 2n=2x=34=10m＋24sm,karyotype belongs to 3B type,the coefficient of karyotype asymmetry is 64.6%.