THE CONTRIBUTION OF BIOLOGICAL CONTROL TOWARDS THE SUSTAINABLE MANAGEMENT OF THE INVASIVE ALIEN PLANT PARTHENIUM HYSTEROPHORUS
Lorraine Strathie, Andrew McConnachie and Alana Den Breeyen
Agricultural Research Council – Plant Protection Research Institute

 

Abstract
As Parthenium hysterophorus (Asteraceae), commonly known as parthenium or famine weed, expands its invasive range in Africa and beyond, it increasingly threatens the conservation of biodiversity as native vegetation is outcompeted and parthenium is unpalatable to wildlife. Parthenium causes severe economic losses for agricultural production, and human and animal health are affected by its allergenic causing properties. Containment of spread and reduction of the density of infestations of parthenium are essential for the management of protected areas. Biological control of parthenium using the plant’s natural enemies introduced from the region of origin in the Americas, has been utilized to good effect in Australia, along with other control measures. Using a combination of biological control agents that affect various plant parts, significant decreases in the abundance and impact of parthenium in most seasons and situations have been achieved in Australia, although severe infestations can still occur. A South African biological control programme has assessed the suitability of several introduced potential agents for release, including a rust fungus (Puccinia xanthii var. parthenii-hysterophorae), a stem-boring weevil (Listronotus setosipennis), a leaf-feeding beetle (Zygogramma bicolorata), a seed-feeding weevil (Smicronyx lutulentus) and a stem-galling moth (Epiblema strenuana). In addition to continuing research in quarantine on potential agents, current efforts are focused on establishing the rust fungus, stem-boring weevil and leaf-feeding beetle, which have been approved recently for release, through the invaded range in KwaZulu-Natal, Mpumalanga and North West provinces, with subsequent evaluation of their establishment and impact. Efforts to implement biological control of parthenium are also underway in Ethiopia and Tanzania. Biological control is anticipated to deliver a sustained level of management of parthenium in the long term. In the interim, it is essential that there is increased awareness of parthenium and the utilization of measures such as chemical control, to reduce the spread and density of infestations.

 

Presentation Topic

THE CONTRIBUTION OF BIOLOGICAL CONTROL TOWARDS THE SUSTAINABLE MANAGEMENT OF THE INVASIVE ALIEN PLANT PARTHENIUM HYSTEROPHORUS

Contact Ms Strathie:
Email Lorraine Strathie