四棱豆的核型和G-带带型研究

用改良ＡＳＧ法在四棱角Ｐｓｏｐｈｏｃａｒｐｕｓ ｔｅｔｒａｇｏｎｏｌｏｂｕｓ（Ｌ．）ＤＣ有丝分裂中期，染色体全长显示了密切邻近的多重Ｇ－带带纹，并进行了核型和Ｇ－带带型分析。核型公式为２ｎ＝１８＝４ｍ＋１４ｓｍ（２ＳＡＴ），核型类型为２Ｂ。Ｇ－带带型分析表明，同源染色体的带纹数目、分布位置、染色深浅基本一致，可以较准确地进行配对；非同源染色体的带型有明显差异，可以准确区分。讨论了改良ＡＳＧ法在核型

STUDIES ON KARYOTYPE AND G-BANDING PATTERNS IN PSOPHOCARPUS TETRAGONOLOBUS (L.) DC

Clear G--bands which were closely adjacent,multiple and distributed along thechromosomes were showed in the mitotic metaphase chromosomes of Psophocarpustetragonolobus (L. ) DC by the advanced ASG method. The karyotype and G--banding patterns were analysed. Its karyotype formula is 2n= 18= 4m 14sm (2SAT), and karyotype asymmetry belongs to 2 B type. The number,position of distribution,staining de-gree of G-bands between homologous chromosomes are basically identical; but nonhomologous chromosomes are distinct in G-band patterns. So chromosome pairing for karyotype analysis could be carried out more accurately and nonhomologous chromosomescould be distinguished easily. The application of the advanced ASG method in karyotypeanalysis and G--banding and the polymorphisms of G--band patterns are discussed.