基于SNP芯片和混池转录组的甘蔗株高QTL定位及候选基因分析

甘蔗是世界上最重要的糖料作物和生物能源作物。株高是甘蔗最重要的产量性状之一。由于现代甘蔗栽培种的高倍性及其基因组的复杂性，鉴定株高数量性状位点（QTL）和开发关联标记辅助育种具有一定的挑战。单核苷酸多态性（SNP）芯片的开发和应用，为甘蔗遗传和基因组研究提供了一个高效、简便、可靠、和新的高通量技术手段。本项目基于前期创制的甘蔗栽培种川糖89-103和ROC22的杂交群体，通过Axiom Sugarcane100K SNP芯片技术构建杂交双亲的高密度遗传连锁图，进而定位甘蔗株高相关的QTL，再通过BSR-seq挖掘不同株高性状的差异表达基因及其他作物株高相关基因的比对，鉴定株高相关的候选基因，开发和验证与株高性状紧密连锁的分子标记。本研究将为甘蔗株高性状提供分子辅助育种标记，为甘蔗其他目标性状的定位提供参考和借鉴，以期推进甘蔗大数据的遗传基础研究，从理论成果走向实践应用，具有重要应用价值。

Sugarcane is an important sugar and bioenergy crop. The plant height is one of the most important yield traits for sugarcane. Due to the high polyploidy and complex genome, there are many challenges for identification of quantitative trait loci (QTLs) and development of molecular markers associated with plant height. Single nucleotide polymorphism (SNP) array technology provides an efficient, convenient and reliable high-throughput method for sugarcane genetic and genomic research. In this study, a mapping population was developed from a cross between two sugarcane cultivars, CT89-103 and ROC22. Two linkage maps of these two parents will be constructed using Axiom Sugarcane100K SNP array, for identifying QTLs related to the sugarcane plant height. Candidate genes controlling the plant height trait and located within the QTL intervals will be identified through comparative analysis between the differentially expressed genes based on BSR-seq associated with sugarcane plant height and the published plant height genes in other crops. According to the sequences of the QTL intervals and candidate genes, molecular markers will be developed and validated. Hopefully, this study will provide some insights and guidance for sugarcane breeding programs and will promote the sugarcane genetic studies from theory to practice.