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German wasp | Vespula germanica

German wasp

Vespula germanica

Coral bush | Ardisia crenata

Coral bush

Ardisia crenata

Purple loosestrife | Lythrum salicaria

Purple loosestrife

Lythrum salicaria

Pom pom weed | Campuloclinium macrocephalum

Pom pom weed

Campuloclinium macrocephalum

Canarybird bush | Crotalaria agatiflora

Canarybird bush

Crotalaria agatiflora

Peanut butter cassia | Senna didymobotrya

Peanut butter cassia

Senna didymobotrya

Rubber vine | Cryptostegia grandiflora

Rubber vine

Cryptostegia grandiflora

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Environmental Programmes

In order to tackle our country’s socio-economic challenges, the government adopted the Outcomes based approach to improve government performance and providing focus on service delivery. find out more

Volatile chemical compounds: attractants or repellents to Falconia intermedia?

Volatile chemical compounds: attractants or repellents to Falconia intermedia?
Samella Ngxande
Biological Control Unit, Zoology and Entomology Department, Rhodes University

Lantana camara is one the most problematic invaders in South Africa invading forest edges, sand dunes and shorelines by forming impenetrable thickets. Lantana camara invasions degrade natural biodiversity, reduce the value of land and, as a consequence, it has been a target for biological control for over 50 years. Recent studies have shown that feeding by one of the agents released against L. camara, Falconia intermedia, induces anti-herbivory response through increased leaf toughness, trichome density and production of volatile chemicals by two varieties of this weed. However, it is not known what specific effects the induced volatile chemicals have on F. intermedia. This study investigated the effect(s) of F. intermedia feeding on the volatile organic chemicals emitted by L. camara varieties, previously unknown. It also sets out to identify the major chemical compounds emitted using Gas Chromatography Mass Spectrometry (GC-MS). Olfactometry assays were conducted to check the effect of different plant varieties on the behaviour of Falconia intermedia. Olfactometry tests are being used to compare the attractiveness of volatile compounds from damaged and undamaged plants to F. intermedia. Preliminary results have showed that 105 (70%) out of 151 insects tested were attracted to undamaged plants. When major chemical compounds have been identified by GC-MS, assays will be done to check the effect of each compound on behaviour of F. intermedia. Once complete, the study will be able to comment on whether volatile chemical compounds contained in L. camara repel biocontrol agents or attract their natural enemies.

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General News Updates

2019 National Symposium on Biological Invasio…

26-02-2019

This is your invitation to South Africa's 2019 National Symposium on Biological Invasions. The convention is hosted by the Centre for Invasion Biology (CIB), University of Stellenbosch, and the Biolo... Read more

2019 Invasive Species Training

22-01-2019

During the past five years (2014-2018), ISSA invasive species trainers have trained 4 000 in the identification of invasive species and laws pertaining to invasive species across South Africa.  ... Read more

Alien Grass Working Group

04-09-2018

Who are we? The South African National Alien Grass Working Group was jointly initiated by the South African Biodiversity Institute (SANBI) and the Centre for Excellence in Invasion Biology (C·I·B) in... Read more

Permits for planting indigenous Cynodon?

01-03-2018

On 16 February, 2018, South Africa's Department of Environmental Affairs issued amendments to the regulations and lists relating to the National List of Invasive Species.  Updates to the draft&n... Read more

Invasive species training 2018 dates released

28-02-2018

Interested in invasive species?  How much do you know about NEMBA invasive species compliance for landowners and organs of state? The South African Green Industries Council (SAGIC) have released... Read more

Communications post for Africa advertised

25-01-2018

The Nature Conservancy has advertised a brand new post:  Communications Manager, Africa Region. Knowledge of invasive species and water would be an asset in this post. See details below:    Job Titl... Read more