Phylogeny of Astragalus in China: molecular evidence from the DNA sequences of 5S rRNA spacer, ITS, and 18S rRNA.

Radix Astragali (root of Astragalus; Huangqi) is a traditional Chinese medicine commonly used as an immunostimulant, hepatoprotective, diuretic, antidiabetic, analgesic, expectorant, and sedative drug. Although the species of Radix Astragali have been defined as Astragalus membranaceus and A. membranaceus var.