Author
Costas Zachariades
zachariadesc@arc.agric.za
Agricultural Research Council
Pietermaritzburg
Coauthors
Lavhelesani E Mawela, Agricultural Research Council, Pietermaritzburg, South Africa
Abstract
Brazilian peppertree, Schinus terebinthifolia (Anacardiaceae), is invasive along the south-eastern coast of South Africa. According to climatic suitability modelling, it has the potential to substantially increase its invasive range within the country. The South African population consists of only ‘haplotype A’ plants, rendering it susceptible to biological control agents which perform well on this haplotype. Pseudophilothrips ichini (Phlaeothripidae), which feeds on the growing stem tips of the plant, was established as the first biocontrol agent on the weed in Florida, USA, after its first release there in 2019. Although other promising potential agents have been investigated for release in Florida, we selected P. ichini because it is easy to rear, has a narrow host range, and can be very damaging to S. terebinthifolia. A thrips culture was established in quarantine in South Africa in 2024, and no-choice host-range trials are underway. Ten genera of Anacardiaceae are native to South Africa, and one of them (Searsia) contains over 90 species. In sub-Saharan Africa, including the western Indian Ocean islands, there are 25 indigenous (many endemic) genera of Anacardiaceae, including 16 in the subfamily Anacardioideae, to which Schinus belongs. The diversity of African Anacardioideae may complicate host-range testing. As an adjunct, a 12-month field survey of S. terebinthifolia is being undertaken along the coast to record plant phenology and its natural enemies.
Keywords
Anacardiaceae
Pseudophilothrips ichini
Schinus terebinthifolia
Host-range trials
Highlights
Brazilian peppertree is increasingly invasive in South Africa
The first candidate biocontrol agent, a stem tip-killing thrips, is in quarantine in South Africa
The large number of closely related native African species may complicate host-range trials