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以药用野生稻(CC)C0t-1 DNA作为探针,对其自身体细胞染色体和栽培稻×药用野生稻杂交后代F1,回交后代BC1以及宽叶野生稻(CCDD),高秆野生稻(CCDD)和斑点野生稻(BBCC)体细胞染色体进行荧光原位杂交实验.在药用野生稻体细胞染色体中,同源染色体呈现相似的C0t-1 DNA杂交带型,并对其核型进行了同源性聚类．对F1(AC)和2个BC1(AAC和ACC)的杂交实验中,在不封阻的情况下,药用野生稻C基因组C0t-1 DNA探针能清晰地鉴别C组染色体,而在A组染色体上信号分布很少,说明A基因组与药用野生稻C基因组中高度重复序列同源性较低．此外,对宽叶野生稻、高杆野生稻和斑点野生稻3个四倍体体细胞染色体进行了FISH分析,在24条C组染色体上均可观察到较强的杂交信号,B和D基因组的24条染色体上信号较少,但在D组染色体上的信号较B组染色体的多,说明D与C基因组的亲缘关系较B与C基因组的近．进一步分析发现,高杆野生稻D组染色体上的杂交信号要比宽叶野生稻D组染色体上的杂交信号多,说明高杆野生稻的D基因组与C基因组的同源性要高,这可能是高秆野生稻和宽叶野生稻同属于CCDD染色体组型但可区分为不同种的原因之一．上述结果表明,C0t-1 DNA具有很强的种的特异性和依赖基因组型的特异性,利用C0t-1 DNA作探针更能有效地对不同基因组进行FISH鉴定．同时,本研究采用F1植株和BC1植株,即1个二倍体和2个三倍体人工选育杂种,与宽叶野生稻、高杆野生稻和斑点野生稻进行了基于C基因组C0t-1 DNA杂交的比较分析,对稻属异源四倍体的可能起源机制进行了初步探讨．
Using CC0 C0t-1 DNA as a probe, F1 hybrids of their somatic cells, hybrid F1 of F1 hybrids and backcross BC1, as well as broad-leaved wild rice (CCDD), high-stalk wild (CCDD) and spot blotchy (Oryza sativa) chromosomes by fluorescence in situ hybridization.Among the somatic chromosomes of O. sativa, homologous chromosomes showed similar C0t-1 DNA hybridization patterns, and their karyotypes Homology clustering was performed. In the hybridization experiment between F1 (AC) and two BC1 (AAC and ACC), the C0t-1 DNA probe of C genome of medicinal wild rice can clearly identify C chromosomes without blocking, while in A The distribution of signal on chromosomes is very small, indicating that A genome has low homology with the highly repetitive sequences of C genome of O. officinalis. In addition, the chromosomes of three tetraploids of wild rice, wild rice and wild rice of O. sativa were analyzed by FISH. Strong hybridization signals were observed on all 24 C chromosomes. The B and D genomes Of the 24 chromosomes signal less, but in the D group of chromosome signals more than the B group of chromosomes, indicating that D and C genomes are more closely related to B and C genomes. Further analysis showed that there were more hybridization signals on the chromosomes of Group D than those on Group D of broad-leaved wild rice, indicating that the homology of D genome and C genome in the high-yielding wild rice is higher, which may be It is one of the reasons why both the high-stalk wild rice and the broad-leaved wild rice belong to the CCDD genome but can be differentiated into different species. The above results show that C0t-1 DNA has a strong species-specific and genomic specificity, and C0t-1 DNA can be used as a probe to identify different genomes more efficiently. At the same time, F1 and BC1 plants, one diploid and two triploid hybrids, were used in this study. Based on C0t-1 DNA hybridization comparative analysis of possible origin of allototic tetraploid rice mechanism was discussed.