Latin name

Utricularia aurea Lour.

Family

Lentibulariaceae

Common name(s)

Bladderwort

Synonym(s)

Utricularia blumei (A. DC.) Miq., U. flexuosa Vahl, U. reclinata Hassk.

Geographical distribution

Asia: Japan.

South and Southeast Asia: Bangladesh, Cambodia, Indonesia, India, Lao PDR, Malaysia, Myanmar, Nepal, Philippines, Sri Lanka, Thailand, and Vietnam.

Rest of the world: China, Australia (southern), and United States.

Morphology

A floating herbaceous plant.

Stem: branched, much elongated, and 30—100—cm—long; stolons long, slender, with many branches; roots at nodes.

Leaf: whorled, 1—6—cm—long; pinnately compound and divided into very numerous filiform segments; most segments have small, nearly globose bladder or insectivorous sacs at the base; sacs 3—4—mm—long, initially reddish but ultimately bluish black, erect, and visible above the water surface.

Inflorescence: 4 to 8—flowered raceme with 8—15—mm—long, orange-yellow corolla.

Fruit: globose capsule up to 5—mm—long and relatively thick and fleshy,

Seeds: numerous, very narrowly winged in all angles, lens- or prism-shaped and 0.75—2—mm—wide, brownish yellow.

Biology and ecology

A perennial aquatic floating herb without roots. Insectivorous and commonly found in ditches, stagnant water, paddy, canals, ditches, reservoirs, slow streams of fresh water, and tidal rice fields. It flowers during February to May, but tends not to flower in rice fields as water is not retained long enough; flowers are seen when it grows in lakes and ditches.

Associated with algae such as Chara sp. and other algae. Propagated by seeds and vegetatively from fragments.

Agricultural importance

Can be a significant weed in rice fields and forms a mesh covering the water surface.

Management

Cultural control: hand weeding reported to be effective in controlling the weed.

Chemical control: reported to be controlled by fluridone.

Selected references

AICAF (Association for International Cooperation of Agriculture and Forestry). 1997. Weeds in the tropics. Tokyo (Japan): Sanbi Printing Co., Ltd. 304 p.

Kaul MK. 1985. Weed flora of Kashmir Valley. Jodhpur (India): Scientific Publishers, P.O. Box 91. 422 p.

Merrill ED. 1976. A flora of Manila. Manila (Philippines): Department of the Interior, Bureau of Science. 491 p.

Moody K. 1989. Weeds reported in South and Southeast Asia. Manila (Philippines): International Rice Research Institute. 442 p.

Noda K, Teerawatsakul M, Prakongvongs C, Chaiwiratnukul L. 1985. Major weeds in Thailand. Bangkok National Weed Science Research Institute Project. 142 p.

Pancho JV, Soerjani M.1978. Aquatic weeds of Southeast Asia: a systematic account of common Southeast Asian aquatic weeds. Bogor (Indonesia): SEAMEO Reg. Cent. for Tropic. Biol. 130 p.

Soerjani M, Kostermans AJGH, Tjitrosoepomo G. 1987. Weeds of rice in Indonesia. Jakarta (Indonesia): Balai Pustaka. 716 p.

Tarver DP. 1985. Status report on Sonar as an aquatic herbicide. Proceedings, Southern Weed Science Society, 38th annual meeting. 394 p.

Taylor P. 1977. Lentibulariaceae. Flora Malesiana Ser. 1 8:275-300.

Contributors

JLA Catindig, RT Lubigan, and DE Johnson