In this review, we present a detailed account of Alternanthera
philoxeroides (alligatorweed), including A. philoxeroides description,
intraspecific variation from native to introduced regions, its life
history strategies, invasion mechanisms, and management strategies.
Alternanthera philoxeroides is a herbaceous amphibious weed of
Amaranthaceae, native to South America, distributed from Buenos Aires
Province (39 degrees S) to south Brazil. It was first described by
Martius in 1826, and consists of several taxa in both its native and
non-native ranges. Current knowledge indicates that two forms of
alligator weed exist in Argentina: A. philoxeroides f. philoxeroides in
the southern range and A. philoxeroides f. angustifolia in the northern
range. In Argentina, both forms set fruits and produce viable seeds.
Alternanthera philoxeroides is now found as a serious weed from tropical
to warm temperate regions, including the USA, China, India, South-East
Asia, Australia and New Zealand. It is thought to have been brought to
China during the 1930s, and later widely cultivated and spread in
southern China as fodder during 1950s. The invasions of alligatorweed in
China have caused considerable concerns, and now it is one of the 12
most harmful alien invasive species in China. Alligatorweed is found on
stationary and slow moving water bodies, creeks, channels, riverbanks
and associated areas that are occasionally flooded. It can also be found
in terrestrial habitats as a pasture weed within urban environments.
Alligatorweed does not produce viable seed in China and reproduces
vegetatively from vegetative fragments (stems, rhizome or root tubes),
which can be transported by water movement, boats, machinery and
vehicles, and in hay. Movement between river catchments is common
because of the human activities. Alligatorweed forms a floating mass
which spreads out over the water. Its growth disrupts the ecology of
banks and shallows and crowds out other plant species, restricts water
flow, increases sedimentation, aggravates flooding, limits access and
use by man and provides a favorable breeding area for disease vectors.
We need better understanding of the biology and ecology of alligatorweed
to assess the efficiency of control methods in any theoretical
framework. According to the knowledge of the life history strategy of
alligatorweed, we suggest that metapopulation theory is a good tool to
improve management efficiency from watershed and regional perspectives.
Mendeley saves you time finding and organizing research
Choose a citation style from the tabs below