Cuscuta Species Identification Based on the Morphology of Reproductive Organs and Complete Chloroplast Genome Sequences

Abstract

The genus Cuscuta (Convolvulaceae) comprises well-known parasitic plants. Cuscuta species are scientifically valuable, as their life style causes extensive crop damage. Furthermore, dried seeds of C. chinensis are used as a Korean traditional herbal medicine. Despite the importance of Cuscuta species, it is difficult to distinguish these plants by the naked eye. Moreover, plastid sequence information available for Cuscuta species is limited. In this study, we distinguished between C. chinensis and C. japonica using morphological characterisation of reproductive organs and molecular characterisation of chloroplast genomes. The differences in morphological characteristics of reproductive organs such as style, stigma, infrastaminal scale, seed shape and testa ornamentation were useful for distinguishing between C. japonica and C. chinensis. Analysis of chloroplast genomes revealed drastic differences in chloroplast genome length and gene order between the two species. Although both species showed numerous gene losses and genomic rearrangements, chloroplast genomes showed highly similar structure within subgenera. Phylogenetic analysis of Cuscuta chloroplast genomes revealed paraphyletic groups within subgenera Monogynella and Grammica, which is consistent with the APG IV system of classification. Our results provide useful information for the taxonomic, phylogenetic and evolutionary analysis of Cuscuta and accurate identification of herbal medicine.

Taxonomic Implications of Leaf Micromorphology Using Microscopic Analysis: A Tool for Identification and Authentication of Korean Piperales

“…Misuse of traditional medicines might result in severe harm to patients [87]. Thus, recent attempts have been made to improve the authentication of medicinal material using microscopic analysis [88][89][90]. Our studied character states revealed that the collected and purchased materials were identical and overlapping.…”

The complete chloroplast genome sequencing analysis revealed an unusual IRs reduction in three species of subfamily Zygophylloideae

“…sutchuenensis in Loranthaceae of Santalales [ 53 ], Epifagus virginiana in Orobanchaceae of Lamiales [ 54 ], Cuscuta chinensis and C . japonica in Convolvulaceae of Solanales [ 55 ]. Smaller chloroplast genomes were also found in some gymnosperms such as Welwitschia mirabilis in Welwitschiaceae of Welwitschiales [ 56 ], and Gnetum ula in Gnetaceae of Gnetales [ 57 ].…”

Comparison among the chloroplast genomes of five species of Chamaerhodos (Rosaceae: Potentilleae): phylogenetic implications

“…These cp genomes have a conserved typically quadripartite structure, in which two inverted repeats (IRs) are separated by a large single‐copy region (LSC) and a small single‐copy region (SSC) (Palmer 1985, Wicke et al 2011). Due to its uniparental inheritance, conserved gene content and structure characteristics (Palmer 1985, Palmer et al 1988, Raubeson and Jansen 2005, Wicke et al 2011), the cp genome is valuable for studies on phylogeny, population genetics and species identification (Korpelainen 2004, Moore et al 2007, Ravi et al 2008, Liu et al 2019, Park et al 2019, Silva et al 2019, Asaf et al 2020, She et al 2020, Wang et al 2020).…”