Li Zhi, Sun Zixin, Ren Tianheng
State key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, China.
College of Agronomy, Sichuan Agricultural University, Chengdu, China.
Front Plant Sci. 2024 Dec 12;15:1501642. doi: 10.3389/fpls.2024.1501642. eCollection 2024.
Rye ( L.) played a very important role in wheat genetic improvement and forage production worldwide. However, since rye is a kind of cross-pollinated plant, high levels of genetic heterozygosity and heterogeneity existed in the genome. Genome-wide variation in repeat sequences is one of the most important reasons for chromosome evolution in rye. High-precision cytological identification can effectively identify the heterochromatin or repeat sequence variations in the rye genome, and the relationship between different rye varieties can be identified while obtaining the FISH-karyotype of different rye varieties. The evolution of rye chromosomes can be analyzed by the variation degree of different probes on rye chromosomes.
All materials were identified by non-denaturing fluorescence hybridization (ND-FISH). Five probes, (AAC), Oligo-pSc119.2-1, Oligo-pTa71A-2, Oligo-pSc200, and Oligo-pSc250 were used to identify rye chromosomes.
15 rye varieties including (cultivated rye and weedy rye), (wild rye), (wild rye), and (wild rye) were examined by five oligonucleotides probes. 92 signal sites and 2074 signal patterns were observed, suggesting that high polymorphisms exist in the different rye genomes. The karyotypes of 15 rye varieties were obtained, the frequency of different signal types at each signal site was calculated and the model diagrams of probes (AAC), Oligo-pSc119.2-1, Oligo-pTa71A-2, Oligo-pSc200 + Oligo-pSc250 were drawn. The results showed that the rate of variation of different chromosomes of rye was not consistent. 1R, 6R, and 7R have higher variation and genetic diversity, while 2R and 3R have lower variation and are more conserved relative to other chromosomes. The results also indicated that has a far genetic distance from other rye species, and might be one of the ancestors of Chinese rye varieties.
Results from this study confirmed rapid chromosome change and high levels of chromosome diversity in rye.
黑麦（L.）在全球小麦遗传改良和饲料生产中发挥了非常重要的作用。然而，由于黑麦是一种异花授粉植物，其基因组中存在高水平的遗传杂合性和异质性。重复序列的全基因组变异是黑麦染色体进化的最重要原因之一。高精度细胞学鉴定可以有效识别黑麦基因组中的异染色质或重复序列变异，在获得不同黑麦品种的荧光原位杂交核型的同时，可以鉴定不同黑麦品种之间的关系。通过黑麦染色体上不同探针的变异程度可以分析黑麦染色体的进化。
所有材料均采用非变性荧光杂交（ND-FISH）进行鉴定。使用五个探针，即（AAC）、寡核苷酸pSc119.2-1、寡核苷酸pTa71A-2、寡核苷酸pSc200和寡核苷酸pSc250来鉴定黑麦染色体。
使用五个寡核苷酸探针检测了包括（栽培黑麦和杂草黑麦）、（野生黑麦）、（野生黑麦）和（野生黑麦）在内的15个黑麦品种。观察到92个信号位点和2074种信号模式，表明不同黑麦基因组中存在高度多态性。获得了15个黑麦品种的核型，计算了每个信号位点不同信号类型的频率，并绘制了探针（AAC）、寡核苷酸pSc119.2-1、寡核苷酸pTa71A-2、寡核苷酸pSc200 + 寡核苷酸pSc250的模式图。结果表明，黑麦不同染色体的变异率不一致。1R、6R和7R具有较高的变异和遗传多样性，而2R和3R变异较低，相对于其他染色体更保守。结果还表明，与其他黑麦物种的遗传距离较远，可能是中国黑麦品种的祖先之一。
本研究结果证实了黑麦染色体的快速变化和高水平的染色体多样性。
