Genome-wide association analysis identified molecular markers and candidate genes for flower traits in Chinese orchid (Cymbidium sinense)  

作　　者：Fengxi Yang Yudi Guo Jie Li Chuqiao Lu Yonglu Wei Jie Gao Qi Xie Jianpeng Jin Genfa Zhu 

机构地区：[1]Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization,Environmental Horticulture Research Institute,Guangdong Academy of Agricultural Sciences,Guangzhou 510640,China

出　　处：《Horticulture Research》2023年第11期193-207,共15页园艺研究（英文）

基　　金：funded by grants from the National Natural Science Foundation of China(31872151,31672184);Guangzhou Science and Technology Project(2022B03J00703);the Innovation Team of Modern Agriculture Industry Technology System in Guangdong Province(2021KJ121);the Guangdong Academy of Agricultural Sciences Discipline Team Construction Project(202127TD,R2020PY-JX018,BZ202006).

摘　　要：The orchid,the champagne of f lowers,brings luxury,elegance,and novelty to nature.Cymbidium sinense is a symbol of gigantic floral variability on account ofwavering shapes and sizes of f loral organs,althoughmarker-trait association(MTA)has not been studied for its f loral traits.We evaluated markers associated with 14 f loral traits of C.sinense through a genome-wide association study(GWAS)of 195 accessions.A total of 65318522 single-nucleotide polymorphisms(SNPs)and 3906176 insertion/deletion(InDel)events were identified through genotyping-by-sequencing.Among these,4694 potential SNPs and 477 InDelswere identified as MTAs at−log10 P>5.The genes related to these SNPs and InDels were largely associated with f loral regulators,hormonal pathways,cell division,and metabolism,playing essential roles in tailoring f loral morphology.Moreover,20 candidate SNPs/InDels linked to 11 genes were verified,8 of which were situated on exons,onewas located in the 5-UTR and twowere positioned in introns.Here,themultitepal trait-related gene RABBIT EARS(RBE)was found to be the most crucial gene.We analyzed the role of CsRBE in the regulation of flower-related genes via efficient transient overexpression in C.sinense protoplasts,and found that the floral homeotic genes CsAP3 and CsPI,as well as organ boundary regulators,including CsCUC and CsTCP genes,were regulated by CsRBE.Thus,we obtained key gene loci for important ornamental traits of orchids using genome-wide association analysis of populations with natural variation.The findings of this study can do a great deal to expedite orchid breeding programs for shape variability.

关 键 词：TRAITS analysis breeding 

分 类 号：S682.31[农业科学—观赏园艺]