通过分析栽培玉米、多年生二倍体大刍草和多年生四倍体大刍草的减数分裂构象,获得了支持玉米属基本染色体数X=5的新细胞遗传学证据。栽培玉米(2n=20)表现出10个二价体的规则减数分裂,故为典型的异源四倍体。此外,在这3个物种的四倍体(2n=20)材料中观察到次级联会现象,那里,在终变期一中期Ⅰ染色体形成1个至5个组,每组含两个二价体,表明部分同源染色体组之间的亲缘关系。 By analyzing meiosis conformation of cultivated maize, perennial diploid herbaceous plants and perennial tetraploid herbaceous plants, new cytogenetic evidence supporting the basic chromosome number of maize genotype X = 5 was obtained. Cultivated maize (2n = 20) showed a regular meiosis of ten bivalents and was therefore a typical allotetraploid. In addition, secondary synapses were observed in the tetraploid (2n = 20) material of the three species, where there were 1 to 5 groups of I chromosomes at the metaphase, each containing two Valence, indicating the relationship between some homologous genomes.