The complete chloroplast genome sequence of Cucumis sativus var. Hardwickii, the wild progenitor of cultivated cucumber

Abstract

The complete chloroplast genome sequence of wild cucumber (Cucumis sativus var. hardwickii) was determined and characterized in this study. The genome is of 155 277 bp in length, containing a pair of inverted repeats regions (IRs) of 25 198 bp, which are separated by a large single-copy region of 86 618 bp and a small single-copy region of 18 263 bp. The wild cucumber chloroplast genome has 130 known genes, including 85 protein-coding genes, 8 ribosomal RNA genes, and 37 tRNA genes. Among these genes, 19 comprise one or two introns. There are 11 tRNA genes present in the IR of the chloroplast genome. Phylogenomic analysis showed that C. sativus var. hardwickii forms a cluster with other Cucumis species with strong bootstrap supports and is closely related to C. sativus var. sativus. This newly sequenced chloroplast genome sequence may provide useful genetic information to explore wild cucumber germplasms for cucumber breeding programs.

Keywords:

• Cucumis sativus var. hardwickii
• chloroplast genome
• wild cucumber

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper. This work was supported by the Top Talents Program of Yunnan Province (20080A009), Project of Innovation Team of Yunnan Province, Hundred Oversea Talents Program of Yunnan Province, and Hundred Talents Program of Chinese Academy of Sciences (CAS) to L. Z. Gao.