Current and potential geographical distribution of the invasive plant Parthenium hysterophorus (Asteraceae) in eastern and southern Africa

Abstract

Parthenium hysterophorus (Asteraceae), of South American origin, is considered to be one of the worldÕs most serious invasive plants, invading Australia, Asia and Africa. As part of an international collaborative project, this study attempted to improve the understanding of the geographical distribution of P. hysterophorus in eastern and southern Africa. The climate modelling program CLIMEX was used to assist in the selection of survey localities. Roadside surveys of the distribution of the weed were conducted in Botswana, Ethiopia, South Africa, Swaziland and Uganda. Prior to these surveys, only limited P. hysterophorus locality records existed; substantially more records were obtained from surveys. Most infestations were high density (>3 plants m )2 ). Distribution records were used to validate the CLIMEX model, which proved a useful tool. This study increased current understanding of the distribution of P. hysterophorus and developed a baseline from which to monitor future spread and abundance of P. hysterophorus. Additional surveys are required in other countries in Africa which are predicted by CLIMEX to be at risk. This will enhance integrated management decisions for the control of a weed which has implications for food security and human health.

Where are the Alien Species? Predictions of Global Plant Species Invasions under Current Environmental Conditions and the Human Footprint

“…However, the distribution of invasive species cannot be delineated with these "natural" variables alone because human activities strongly affect the dispersal of alien species directly and indirectly. Direct influence includes the introduction of alien species outside their native geographic ranges to obtain food, medicine, recreation, and other commercial benefits [12]. Indirect influence, such as anthropogenic elimination of native species, can promote alien species invasion; eliminating native species is advantageous for alien species when competition exists [13].…”

Parthenium Hysterophorus. L. (Asteraceae) : A Boon or Curse? (A Review)

“…Australia has advantages such as being a nation-continent, having achieved early biocontrol successes known to the public, having a unique native flora and enjoying political enthusiasm for biological control 58 . Similarly Parthenium invaded in national wildlife parks have also been reported in geographical distribution of Parthenium hysterophorus in 1994 14 southern India 59 . Parthenium spread over agricultural land, grazing land and highways.…”

Kinetic Study of the Acid Hydrolysis of Parthenium hysterophorus L. for xylose yield in the Production of Lignocellulosic ethanol

“…Dispersal of seed takes place via vehicle, water, animals, farm machinery and wind. Disturbed habitats such as roadsides and railway tracks, stockyards, buildings surroundings and fallow agricultural land are particularly suitable for growing P hysterophorus due to a lack of interspecies competition [3].…”