State Key Laboratory of Crop Biology, Shandong Agricultural University, Taian, 271018, Shandong, China.
College of Agronomy, Shandong Agricultural University, Taian, 271018, Shandong, China.
Mol Genet Genomics. 2019 Feb;294(1):35-45. doi: 10.1007/s00438-018-1486-6. Epub 2018 Aug 29.
Miscanthus is recognized as a promising lignocellulosic crop for the production of bioethanol and bioproducts worldwide. To facilitate the identification of agronomical important traits and establish genetics knowledge, two genetic maps were developed from a controlled interspecific cross between M. floridulus and M. sacchariflorus. A total of 650 SSR markers were mapped in M. floridulus, spanning 19 linkage groups and 2053.31 cM with an average interval of 3.25 cM. The map of M. sacchariflorus comprised 495 SSR markers in 19 linkage groups covering 1684.86 cM with an average interval of 3.54 cM. The estimation on genome length indicated that the genome coverage of parental genetic maps were 93.87% and 89.91%, respectively. Eighty-eight bi-parental common markers were allowed to connect the two maps, and six pairs of syntenic linkage groups were recognized. Furthermore, quantitative trait loci (QTL) mapping of three agronomic traits, namely, plant height (PH), heading time (HT), and flowering time (FT), demonstrated that a total of 66 QTLs were identified in four consecutive years using interval mapping and multiple-QTL model. The LOD value of these QTLs ranged from 2.51 to 10.60, and the phenotypic variation explained varied from 9.50 to 37.10%. QTL cluster in syntenic groups MF19/MS7 contained six stable QTLs associated with PH, HT, and FT. In conclusion, we report for the first time the genetic mapping of biomass traits in M. floridulus and M. sacchariflorus. These results will be a valuable genetic resource, facilitating the discovery of essential genes and breeding of Miscanthus.
芒属植物被认为是一种很有前途的木质纤维素作物，可用于生产生物乙醇和生物制品，在世界范围内得到广泛应用。为了促进农艺性状的鉴定和遗传知识的建立，本研究利用芒属植物佛罗里达芒和荻的杂交后代，分别构建了两个遗传图谱。在佛罗里达芒中，共定位了 650 个 SSR 标记，覆盖 19 个连锁群，总长 2053.31cM，标记间平均距离为 3.25cM。荻的遗传图谱包含 495 个 SSR 标记，分布在 19 个连锁群上，总长 1684.86cM，标记间平均距离为 3.54cM。基因组大小估计表明，亲本遗传图谱的基因组覆盖率分别为 93.87%和 89.91%。88 个双亲共有的标记可以将两个图谱连接起来，并且识别出了 6 对对应的连锁群。此外，通过区间作图和多 QTL 模型，对 3 个农艺性状（株高、抽穗期和开花期）进行了 QTL 作图，连续 4 年共鉴定到 66 个 QTL。这些 QTL 的 LOD 值范围为 2.51 到 10.60，表型变异解释率为 9.50 到 37.10%。在对应的连锁群 MF19/MS7 中，有 6 个与 PH、HT 和 FT 相关的稳定 QTL 簇。总之，本研究首次报道了佛罗里达芒和荻的生物量性状的遗传图谱。这些结果将为芒属植物的重要基因的发现和杂交育种提供有价值的遗传资源。
