Pueraria lobata (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Pueraria lobata (Willdenow) Ohwi

Family: Leguminosae

Synonyms

• var. lobata : Pueraria thunbergiana (Sieb. & Zucc.) Bentham, P. hirsuta (Thunb.) Matsumura, P. triloba (Houtt.) Makino;

• var. montana (Lour.) van der Maesen: Dolichos montanus Lour., Pueraria tonkinensis Gagnepain, P. montana (Lour.) Merrill;

• var. thomsoni (Bentham) van der Maesen: Pueraria thomsoni Bentham.

Vernacular names

• General: kudzu (En).

• var. lobata : Kudzu, Japanese arrowroot (En). Koudzou (Fr)
• Indonesia: bitok (Madurese), tobi (Sundanese), tebi (Kangean)
• Papua New Guinea: owitu (Asaro), kopitu (Kainantu), oka moi (Medlpa)
• Philippines: baai (Igorot), tahaunon (Manubo)
• Thailand: tamyakhrua
• Vietnam: cu nang, cu sắn dây.

• var. montana : Taiwan kudzu (En)
• Laos: chüa tau kung (northern), khauz pièd (northern)
• Vietnam: dây cae lan, dây dan, sắn dây.

• var. thomsoni : Thomson's kudzu (En)
• Thailand: phakphit
• Vietnam: dây cát căn, sắn dây.

Distribution

From eastern India throughout South-East Asia, China, Japan and Pacific Islands. Now widespread in other tropical and subtropical areas, cultivated and often naturalized. Var. lobata , originally from China and Japan, is the main variety introduced elsewhere. Var. montana originates from Indo-China, southern China, Taiwan and the Philippines, var. thomsoni from north-eastern India to Indo-China and the Philippines.

Uses

Kudzu produces edible tubers, useful stem fibres, its leaves, shoots and flowers can be used as vegetable and for silage or hay, and it is a useful erosion-controlling soil cover, shade plant and medicinal plant. The tuber is esteemed for its fine starch, used especially in China, Japan and Papua New Guinea for sauces, soups, jelled salads, noodles, porridges, jelly puddings, confectionary and beverages. Japan produces over 300 t per year. Elsewhere in South-East Asia the tubers are used in times of famine. The stem fibres are used for binding (ropes), weaving (clothes, fishing lines, baskets) and for paper production. It is excellent for fodder and silage, if mixed with grass. It is effective for erosion control, provided its growth is controlled well; its aggressive growth may lead to entire forests being covered and trees dying, as has been experienced in the United States. Medicinally the starch is used in Japan to restore intestinal and digestive disorders, taken in soups or teas. Tea from the tubers is used in China against colds, influenza, diarrhoea, dysentery and hangovers. The flowerbuds are used as a diaphoretic and febrifuge medicine. Kudzu is also popular as an ornamental climber with fragrant flowers.

Observations

Perennial, pubescent, woody climber with very large oblongoid tubers up to 2 m long, 18-45 cm in diameter, weighing up to 180 kg when old. Branches strong, up to 30 m long and up to 10 cm in diameter. Leaves alternate, pinnately trifoliolate; petiole 8-13(-21) cm long, rachis 1.5-7 cm long, petiolules 4-10 mm; leaflets ovate to orbicular, 8-26 cm × 5-22 cm, entire to trilobed. Inflorescence usually an unbranched elongate pseudoraceme up to 35 cm long with 3 flowers per node; calyx campanulate with 5 unequal teeth; petals purplish to blue or pink, often with a yellow or green spot, up to 25 mm long; stamens 10, monadelphous or with one free stamen. Fruit a flattened oblongoid pod, straight to falcate, 4-13 cm × 0.6-1.3 cm, golden-brown hairy, with 5-15 seeds. Seed flattened-ovoid, 4-5 mm × 4 mm × 2 mm, red-brown with black mosaic. Germination epigeal, first two leaves simple and opposite.

P. lobata occurs in thickets, forests, roadsides, pastures, hedges, on dry or moist, poor or rich soils, more common in the lowlands but up to 2000 m altitude. Outside its native area, seed is not usually formed. Propagation is mainly by planting young stem cuttings almost horizontally. Tubers can be harvested about 1 year after planting the cuttings. If left longer in the soil they can become very large. For fodder production, first harvest is possible in the second year, full production is reached from the third year onwards.

P. lobata is extremely variable and 3 varieties have been distinguished, although intermediates occur. The main distinguishing characteristics are flower size, leaflet form and fruit size.

• var. lobata : flowers 12-20 mm long, leaflets usually trilobed, fruits 5-13 cm × 7-12 mm;

• var. montana : flowers up to 12 mm long, leaflets usually entire, fruits 4-10 cm × 6-9 mm;

• var. thomsoni : flowers 20 mm or longer, leaflets usually trilobed, fruits 8-13 cm × 9-13 mm.

Other tuberous Pueraria species have or might have similar possibilities (e.g. P. candollei Graham ex Bentham from India, Bangladesh, Burma (Myanmar) and Thailand; P. edulis Pampanini from India and China; P. mirifica Airy Shaw & Suvat. from Thailand; P. tuberosa (Roxb. ex Willd.) DC. from India, Nepal and Pakistan).

Selected sources

1, 3, 8, 13, 17, 23, 24, 30, 32, 40, 43, 62, 67, 68, 79, 90, 91.

Authors

L.E. Groen, J.S. Siemonsma & P.C.M. Jansen