Damasonium minus
From Wikipedia, the free encyclopedia
| Damasonium minus | |
|---|---|
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Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Order: | Alismatales |
| Family: | Alismataceae |
| Genus: | Damasonium |
| Species: | D. minus |
| Binomial name | |
| Damasonium minus | |
| Synonyms[2] | |
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Damasonium australe Salisb. (nom. illeg.) nom. superfl. | |
Damasonium minus is a species of flowering plant in the water-plantain family known by the common names starfruit and star-fruit (not to be confused with the cultivated starfruit).[1] It is native to Australia, where it occurs everywhere except the Northern Territory.[1][3] It is perhaps best known as an agricultural weed. It is a major weed of Australian rice crops.[4][5][6]
This species is an emergent aquatic plant. It is an annual or short-lived perennial herb growing up to a meter tall. The floating or emergent leaves have blades up to 10 centimeters long by 4 wide and lance-shaped to heart-shaped. They are borne on petioles up to 30 centimeters long. The branching inflorescence has whorls of flowers. Each flower has tiny green sepals and white or pink petals a few millimeters long. The star-shaped aggregate fruit is made up of follicles containing seeds.[3][7]
This plant grows in habitat with slow-moving and still water, such as swamps.[3]
In agriculture, this plant has been called "the most important broadleaf weed in the Australian rice crop."[5] Most rice is grown in Victoria and New South Wales.[5] This weed has been controlled with the herbicide bensulfuron-methyl, but it has become less effective as herbicide-resistant strains have evolved.[5] A pathogenic fungus, Rhynchosporium alismatis, was discovered on the plant, and it has become an option for biological control as a mycoherbicide. The fungus causes chlorosis and necrosis of the leaves on the mature plant and stunting of immature individuals. If immature weeds in a paddy are stunted, the rice plants may have a competitive advantage.[4] The fungus can kill seedlings, and if it infects the inflorescence of the weed it can reduce seed weight and viability.[8] The fungus can also help control another rice weed, Alisma lanceolatum.[6]