In botany, a diaspore is a plant dispersal unit consisting of a seed or

spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...

plus any additional tissues that assist dispersal. In some seed plants, the diaspore is a seed and fruit together, or a seed and elaiosome. In a few seed plants, the diaspore is most or all of the plant, and is known as a tumbleweed. Diaspores are common in weedy and ruderal species. Collectively, diaspores, seeds, and spores that have been modified for migration are known as ''disseminules''.

Role in dispersal

A diaspore of seed plus elaiosome is a common adaptation to seed dispersal by ants ( myrmecochory). This is most notable in

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

n and South African sclerophyll plant communities. Typically, ants carry the diaspore to their nest, where they may eat the elaiosome and discard the seed, and the seed may subsequently germinate. A Taraxacum Ruderalia dandelion clock

A diaspore of seed(s) plus fruit is common in plants dispersed by

frugivore A frugivore is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance an ...

s. Fruit-eating bats typically carry the diaspore to a favorite perch, where they eat the fruit and discard the seed. Fruit-eating birds typically swallow small seeds but, like bats, may carry larger seeded fruits to a perch where they eat the fruit and discard the seed. Diaspores such as

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...

s and

samara Samara ( rus, Сама́ра, p=sɐˈmarə), known from 1935 to 1991 as Kuybyshev (; ), is the largest city and administrative centre of Samara Oblast. The city is located at the confluence of the Volga and the Samara (Volga), Samara rivers, with ...

e are dispersed primarily by wind; samaras are dispersed also by sailing or tumbling as they fall in still air.

Drift fruit __NOTOC__ Drift seeds (also sea beans) and drift fruits are seeds and fruits adapted for long-distance dispersal by water. Most are produced by tropical trees, and they can be found on distant beaches after drifting thousands of miles through oce ...

s and some others are dispersed by water. Tumbleweeds are dispersed by wind, sometimes over very long distances. These occur in a variety of weedy and ruderal species native to

steppe In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the temperate grasslands, ...

s and

desert A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...

s. Grasses have various units of dispersal: rarely the caryopsis alone, often a diaspore. Disarticulation occurs below, between, or above the glumes and at all nodes. Although in some species the diaspore is a foxtail, in a few (the "tumble grasses") it is like a tumbleweed.

References

{{fruits Plant morphology Plant reproductive system Ecology

Role in dispersal

See also

References