It has been just over four years since the SANBI-funded postdoctoral project ‘Monitoring plant health in sentinel sites: botanical gardens and arboreta’ started. The project was initiated in 2016 by Dr Trudy Paap under the leadership of Prof. Mike Wingfield, with the aim of improving surveillance and identification of pest and pathogen risks using botanical gardens and arboreta in South Africa as sentinel sites. Dr Paap run the project from mid-2016 to end of 2018. Currently, the project is in its second term (2019-2020) and being run by Dr Mesfin Gossa under the leadership of Profs. Mike Wingfield, Bernard Slippers, Brett Hurley, and Dr Trudy Paap. During the course of the project, many pest and pathogen issues have been identified from the different gardens, with some of these representing first reports for the country. These include the Polyphagous Shothole Borer (PSHB) and its fungal symbiont, several Phytophthora spp., scale insects, cypress aphids, aloe snout beetles and cycad stem borers. 

Dr. Gossa and Dr. Paap hosted a one-hour webinar on 28 July. The topic of the webinar was ‘Plant Health in Botanical Gardens’ and included a presentation by Dr Gossa and a discussion session led by Dr Paap. Horticulturalists, curators and managers from various gardens, including Durban Botanic Gardens, Arderne Gardens, and Free State, Kirstenbosch and Pretoria National Botanical Gardens attended the webinar. An update on the SANBI-funded sentinel plant project was presented. Topics of discussion included the global burden of pests and pathogens on plant health, factors that exacerbate pest and pathogen threats, knowledge gaps on emerging alien and native pests and pathogens, the importance of surveillance and monitoring and the value of botanical gardens as sentinel sites for pest and pathogen surveillance. There was also an opportunity for garden staff to raise any plant health issues encountered in the gardens during the lockdown period.