鹅观草属三个种的形态变异与核型的研究

本文通过对鹅观草属的三个种:鹅观草(Roegneria kamoji Ohwi)、纤毛鹅观草(R. ciliars (Trin.) Nevski)和竖立鹅观草(R. japonensis(Honda)Keng)的形态学比较和核型分析研究了该三个种的系统关系。R. kamoji与R. ciliaris、R. japonensis形态上的差异明显,而后二个种差异甚小,难以进行划分。R. kamoji的核型公式为:2n=6x=42=30m+8sm+4SAT;R. ciliaris为:2n=4x=28=18m+6sm+4SAT;R. japonensis为:2n=4x=28=18m+6sm+4SAT。t-测验的结果表明R. ciliaris与R. japonensis的核型无显著差异。因此笔者认为R. ciliaris和R. japonensis应合并为一种系内的分类群。

THE STUDIES OF MORPHOLOGICAL VARIATIONS AND KARYOTYPE ANALYSIS ON THE THREE ROEGNERIA SPECIES

The biosystematic relationships among Roegneria kamoji Ohwi, R. ciliaris (Trin.) Ncvski and R. japonensis (Honda) Keng in the tribe Triticeae Dumortier were studied in the present paper by the methods of morphological comparison and karyotype analysis. Morphologically, R. kamoji was quite different from the other two species, i. e. R. ciliaris and R. japonensis. But there was very slight disparity between the latter two so sies. Therefore, the classification of the two species was very difficult. Cytelogically, the karyotype formulae of the three species were as follows. R. kameji, 2n = 6x = 42 = 30m 4+ 8sm + 4SAT;R. ciliaris, 2n= 4x = 28 = 18 m + 6sm+ 4SAT; R. japonensis, 2n = 4x = 28 = 18m + 6sm + 4SAT. The karyotype of R. ciliaris and R. japonensis showed nonsignificant difference from the analysis of t-test, while the karyotype of R. kamoji was substantially different from those of the other two species. Based on above-mentioned results, the authers suggest R. ciliaris and R. japonensis be combined into one species.