石竹属花卉花序分枝关键基因及其调控机制研究

我国已成为世界最大的花卉生产国，但花卉品质严重制约着我国鲜切花产品的国际化步伐，而花序发育过程则是影响切花品质的关键。石竹属花卉为世界四大切花之一，其花序发育机理尚不清楚。项目前期发现石竹属花卉花序分枝性状由一对不完全显性基因控制，超聚型对散枝型为不完全显性。利用F2群体对分枝性状进行混池测序，筛选出与花序分枝紧密连锁SNP位点116个、InDel位点32个。在紧密连锁区域16.5M内设计分子标记，用侧翼标记扫描F2代大群体，筛选交换单株。基于此，本项目拟设计内侧标记扫描交换单株、缩小区间，精细定位目的基因，结合重测序及转录组等确定花序分枝关键基因；通过VIGS、实时定量和遗传转化等进行关键基因功能验证；利用酵母双杂、BiFC及转化植株转录组分析等，探究关键基因互作蛋白及调控途径，明确网络调控机制。以期为丰富观赏植物资源、品种改良提供基因储备；为花卉品质精准调控等生产栽培技术奠定理论基础。

China has become the world's largest flower producer, but the quality of cutting flowers severely restricts the internationalization progress. Inflorescence development is the key factor affecting cutting flower quality. Dianthus genus flowers are world-famous ornamental plants, but the inflorescence development mechanism has not been reported. The branching trait of inflorescence is controlled by an incomplete dominant gene based on genetic analysis of hybrid offsprings. Compared of ‘less branch’, the ‘much branch’ types is incomplete dominant. The F2 generation ‘less branch’ and ‘much branch’ inflorescence branching extreme pools were constructed. After the Bulk segregant analysis the difference sites were calculated, 116 closely linked SNPs and 32 InDels were selected. Molecular markers were designed within 16.5M of the tightly linked region. The F2 expanded generation was scanned with flanking markers to screen for exchanged plants. Based on this, the inner markers will gradually design to scan the exchanged plants in this project, narrow the localization area, and determine the key genes of inflorescence branching in combination with the transcriptome and resequencing analysis. Then verify the function of the target gene by VIGS, real-time quantification PCR, in-situ hybridization, and genetic transformation etc.. Analysis of key interaction proteins and regulatory pathways of the brancah gene was performed by Yeast two-hybrid system and BiFC. RNA-seq analysis of transformed plants will also be used to clarify the regulatory mechanism of the target gene network. Hope the results can provide genetic resources for enriching ornamental plant flower types and varieties. And make a theoretical foundation for production and cultivation techniques such as ‘precise regulation’ of flower quality.