摘要
The marvelously diverse Orchidaceae constitutes the largest family of angiosperms.The genus Cymbidium in Orchidaceae is well known for its unique vegetation,floral morphology,and flower scent traits.Here,a chromosomescale assembly of the genome of Cymbidium ensifolium(Jianlan)is presented.Comparative genomic analysis showed that C.ensifolium has experienced two whole-genome duplication(WGD)events,the most recent of which was shared by all orchids,while the older event was the t event shared by most monocots.The results of MADS-box genes analysis provided support for establishing a unique gene model of orchid flower development regulation,and flower shape mutations in C.ensifolium were shown to be associated with the abnormal expression of MADS-box genes.The most abundant floral scent components identi fied included methyl jasmonate,acacia alcohol and linalool,and the genes involved in the floral scent component network of C.ensifolium were determined.Furthermore,the decreased expression of photosynthesis-antennae and photosynthesis metabolic pathway genes in leaves was shown to result in colorful striped leaves,while the increased expression of MADS-box genes in leaves led to perianth-like leaves.Our results provide fundamental insights into orchid evolution and diversi fication.
基金
The authors acknowledge support from the National Key Research and Development Program of China(no.2019YFD1000400)
the National Natural Science Foundation of China(no.31700618)
the Outstanding Young Scientific Research Talent Project of Fujian Agriculture and Forestry University(no.xjq201910)
the Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilizati on Construction Funds(nos.115/118990050,115/KJG18016A)
the Furopean Research Council(ERC)under the Furopean Union's Horizon 2020 research and innovation program(grant agreement No 833522).
