Pueraria is a genus of 15–20 species of leguminous flowering plants in the family Fabaceae (order Fabales), native to south, east, and southeast Asia, as well as New Guinea and northern Australia. Plants in the genus take the form of lianas, shrubs, or twining climbing herbs, typically bearing large tuberous roots that have long been used as food and medicine across Asia.
The genus is best known for kudzu (Pueraria montana var. lobata), a vigorous vine sometimes called Japanese arrowroot, which became notorious as an invasive species across the southeastern United States after its introduction in the 19th century. Other members include Pueraria tuberosa (the type species), prized in Ayurvedic medicine for its starchy tuber, and Pueraria edulis, cultivated for its edible roots in parts of China.
Typical habitats span seasonally dry tropical and subtropical forest, rainforest, forest margins, and scrub vegetation, often on limestone outcrops and in rocky areas. The genus was named in honour of Marc Nicolas Puerari, a 19th-century Swiss botanist.
Taxonomically, Pueraria as traditionally circumscribed is polyphyletic — molecular studies, particularly Egan & Pan (2016), revealed that its species belong to multiple distinct lineages within the tribe Phaseoleae. That work reorganised the genus into five clades: a monophyletic core (Pueraria sensu stricto) and four segregate genera — Neustanthus, Teyleria, Toxicopueraria, and Haymondia — to which many former Pueraria species were transferred.
Etymology
The genus name Pueraria honours Marc Nicolas Puerari (1766–1845), a Swiss botanist of the 19th century. The name was applied by the botanists who formally described the genus in recognition of his contributions to botany.
Distribution
Pueraria species are native to south, east, and southeast Asia (including the Indian subcontinent, China, Japan, and Southeast Asia), with additional species extending to New Guinea and northern Australia. Pueraria montana var. lobata (kudzu) has become widely naturalised as an invasive species in the southeastern United States and parts of Europe.
Ecology
Plants grow as lianas, shrubs, or climbing herbs in a range of tropical and subtropical habitats: seasonally dry forests, rainforests, forest margins, and scrub vegetation, with a notable affinity for limestone outcrops and rocky terrain. As legumes, Pueraria species fix atmospheric nitrogen through root nodule symbioses, which contributes to the vigorous growth that makes kudzu particularly competitive in disturbed habitats.
Cultural Uses
Several Pueraria species have been used in Asian traditional medicine and as food crops for centuries. Pueraria tuberosa is an important plant in Ayurvedic medicine. Pueraria montana var. lobata (kudzu) yields edible starchy roots consumed as arrowroot-type starch and has been used in traditional Chinese medicine; its vines were also introduced to the United States in the 19th century for erosion control and cattle fodder before becoming invasive. Pueraria edulis is cultivated in parts of China for its edible tuberous roots.
Taxonomy Notes
As traditionally circumscribed, Pueraria is polyphyletic. Molecular phylogenetic research by Egan & Pan (2016), published in Phytotaxa, resolved the genus into five distinct clades within tribe Phaseoleae. The core monophyletic clade, Pueraria sensu stricto, includes the type species P. tuberosa and most accepted species. Four other clades were elevated to or reassigned to separate genera: Neustanthus (including the former P. phaseoloides), Teyleria, Toxicopueraria, and Haymondia. Kew's Plants of the World Online database accepts this revised circumscription. Some species remain provisionally retained pending sufficient material for molecular sequencing.
