First report of Fusarium wilt and pink rot of Phoenix canariensis in South Africa

Abstract

Canary Island date palm, Phoenix canariensis, is a popular ornamental species commonly planted in urban areas worldwide, including South Africa. In November 2023, symptoms typical of Fusarium wilt were detected on ornamental palms at the Waterfront in Cape Town, Western Cape Province, South Africa. Samples were collected from three wilting palms with one sided frond death and pink sporulation on the bark. Isolations to culture media yielded two fungal species, which were confirmed based on DNA sequence data as Fusarium oxysporum f.sp. canariensis (Foc) and Nalanthamala vermoesenii. Fusarium wilt, caused by Foc, is among the most serious diseases of these palms. There is no effective treatment for this vascular wilt disease and infected palms inevitably die. Pink rot, caused by N. vermoesenii, is commonly found as a secondary infection associated with Fusarium wilt in P. canariensis. This is the first detection of the Fusarium wilt and pink rot pathogens in South Africa.