Table 1. Statistics on the basic features of the chloroplast genomes of five Ulmus species.

	Ulmus pumila	Ulmus davidiana Planch. var.	Ulmus macrocarpa	Ulmus davidiana	Ulmus laciniata
Length (bp)	159082	159411	159439	159453	158953
GC content (%)	35.57	35.57	35.56	35.55	35.57
AT content (%)	64.43	64.43	64.44	64.45	64.43
LSC length (bp)	88103	88508	88547	87633	88032
SSC length (bp)	18850	18868	18853	18835	18846
IR length (bp)	26064	26017	26019	26492	26037
Gene number	137	145	142	143	139
Gene number in IR regions	37	39	39	40	37
Protein-coding gene number	83	89	88	88	85
Protein-coding gene (%)	60.58	61.38	61.97	61.54	61.15
rRNA gene number	8	8	8	8	8
rRNA (%)	5.84	5.52	5.63	5.59	5.76
tRNA gene number	46	48	46	47	46
tRNA (%)	33.58	33.1	32.39	32.87	33.09