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本文分析了5个拟直立型组和2个花生组野生种的染色体组型:7个种皆为二倍体2n=2x=20,染色体长度介于2.69～6.47μm之间,臂比为1.07～2.54;在10对染色体中,8、9对具中部着丝点,其他具近中部着丝点。根据染色体长度、臂比及随体的位置,可把每个种(系)中6～10对染色体加以区分。研究中还把染色体的臂比作为独立性状,分析了供试种(系)间的遗传距离(D~2)。其中拟直立型组5个种(系)间的D~2差异很大(0.136～11.523),说明该组在进化过程中染色体组型已出现较大分化和变异。拟直立型组与花生组在染色体组型上虽有一定相似性,但差异更显著,首先,花生组中“A”“B”两个标志染色体在拟直立型组中不存在,其次是对称性优于拟直立型组。文中对上述两个组的进化程度作了进一步的讨论。
In this paper, we analyzed the karyotypes of five wild-type and two peanut-type wild species: 7 species were diploid 2n = 2x = 20, chromosome length was 2.69-6.47μm, arm ratio was 1.07 ~ 2.54; Of the 10 pairs of chromosomes, 8,9 pairs have central centromere and others have centromere. According to chromosome length, arm ratio and the location of the satellite, each species (lines) 6 to 10 pairs of chromosomes to be distinguished. In the study, the arm ratio of chromosomes was also used as an independent trait to analyze the genetic distance (D ~ 2) for the tested species (lines). Among them, D ~ 2 among 5 species (lines) of quasi-erect type were very different (0.136 ~ 11.523), which indicated that the chromosome constitution of this group had a great differentiation and variation during evolution. There were some similarities between the quasi-upright and peanut groups in the genotypes of the chromosomes, but the difference was more significant. First, the two “A” and “B” markers in the peanut group did not exist in the quasi-erect group, followed by the symmetry Sex is better than the proposed erect type group. The paper further discusses the evolution of the above two groups.