Uncovering the phylogeography of Schinus terebinthifolia in South Africa to guide biological control

Kim Canavan; Nwabisa L Magengelele; Iain D Paterson; Dean A Williams; Grant D Martin

doi:10.1093/aobpla/plab078

Uncovering the phylogeography of Schinus terebinthifolia in South Africa to guide biological control

AoB Plants. 2021 Dec 23;14(1):plab078. doi: 10.1093/aobpla/plab078. eCollection 2022 Feb.

Authors

Kim Canavan¹, Nwabisa L Magengelele^{1

2}, Iain D Paterson¹, Dean A Williams³, Grant D Martin^{1

4}

Affiliations

¹ Centre for Biological Control, Department of Entomology and Zoology, Rhodes University, Makhanda, PO Box 94, 6140, South Africa.
² Environmental Learning Research Centre, Department of Education, Rhodes University, Makhanda 6140, South Africa.
³ Department of Biology, Texas Christian University, Fort Worth, TX 76129, USA.
⁴ Afromontane Research Unit and Zoology Department, University of the Free State, Qwaqwa Campus, Phuthaditjhaba 9866, South Africa.

Abstract

Schinus terebinthifolia is a problematic invasive alien plant (IAP) in South Africa that is a high priority target for biological control. Biological control has been implemented in the states of Florida and Hawaii (USA), where S. terebinthifolia is also an IAP. Phylogeographic work determined that there have been multiple introductions of two lineages (haplotype A and B) into the USA. Haplotype A was introduced to western Florida and Hawaii, while haplotype B was introduced to eastern Florida. Haplotypes A and B have subsequently hybridized in Florida, resulting in novel plant genotypes. Biological control agents in the USA are known to vary in efficacies on the two different haplotypes and hybrids. This study used molecular techniques to uncover the source populations of S. terebinthifolia in South Africa using chloroplast DNA and microsatellites. Populations from the introduced ranges in Florida (east, west and hybrids) and Hawaii were included (n = 95). All South Africa populations (n = 51) were found to be haplotype A. Microsatellite analysis determined shared alleles with western Florida and Hawaiian populations. The likely source of South African S. terebinthifolia was determined to be western Florida through the horticultural trade. These results will help guide a biological control programme to source agents that perform well on these populations in the USA. Furthermore, the presence of only one haplotype in South Africa highlights the need to ensure no further introductions of other haplotypes of the plant are made, in order to avoid similar hybridization events like those recorded in Florida.

Keywords: Hybridization; Schinus terebinthifolia; invasive species; microsatellites; phylogeography.