Buchnera (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Buchnera L.

Protologue: Sp. pl. 2: 630 (1753); Gen. pl. ed. 5: 278 (1754).

Family: Scrophulariaceae

Chromosome number: x= unknown

Buchnera comprises approximately 100 species and occurs in all tropical and subtropical regions. Southern and eastern Africa are richest in species (over 50). South-East Asia is comparatively poor, with 3 species in Indo-China and Thailand, and about 5 in the Malesian region (1 in Java, 1 in the Philippines, 4 in New Guinea).

Some uses have been recorded for Buchnera species in traditional medicine in South-East Asia. In Papua New Guinea, whole plants of B. ciliata are used as a sedative during childbirth, whereas in Thailand, Vietnam and southern China whole plants of B. cruciata are applied to cure cough, asthma, epilepsy and ulcers, and to prevent anaemia.

In Tanzania, B. hispida Buch.-Ham. ex D. Don is powdered and mixed with castor-oil, and applied externally to scabies and eczema.

As in many other Scrophulariaceae , mannitol is present in Buchnera .

Annual or perennial hemiparasitic herbs; stems usually erect and simple or laxly branched, terete. Leaves opposite, occasionally alternate, lower ones often rosulate, simple, linear to ovate, entire to coarsely dentate, sessile or shortly petiolate; stipules absent. Inflorescence terminal, spicate, 4-angled, densely flowered; bracts large, subtending and largely covering the flowers. Flowers bisexual, sessile, with 2 small bracteoles, 5-merous; calyx tubular, equally lobed; corolla with slender cylindrical tube, with subequal, spreading lobes; stamens 4, adnate at the middle of the corolla tube, short, slightly didynamous; ovary superior, 2-celled, style filiform, stigma clavate. Fruit an ovoid to oblong capsule, loculicidally 2-valved, many-seeded. Seeds cylindrical or fusiform, longitudinally striate.

Buchnera is found in open forest and grassland, up to 1600 m altitude.

Some species, e.g. the African B. hispida , are facultative root parasites of grasses and cereals, and occasionally may be pests in crops (especially maize and sorghum). However, they are not of economic importance.

The South-East Asian Buchnera species do not seem to be liable to genetic erosion. They are not restricted to vulnerable habitats, and are usually widely distributed. However, some species, such as B. ciliata , are more or less narrow endemics, and overcollecting may easily result in too high pressure on populations.

The lack of data on chemistry and pharmacological activity makes it impossible to predict whether the uses of Buchnera in local medicine will have wider application.

120, 331.

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Wongsatit Chuakul, Noppamas Soonthornchareonnon & Orawan Ruangsomboon