Abstract:
Some species of the Botryosphaeriaceae are capable of infecting a broad range of host
plants. We studied the species diversity of Botryosphaeriaceae associated with marula
(Sclerocarya birrea subsp. caffra, Anacardiaceae) trees in South Africa over two seasons,
as well as species common to both S. birrea and adjacent mango (Mangifera indica,
Anacardiaceae) trees in a subset of sites. Gene flow amongst populations of
Botryosphaeriaceae shared on these tree species was tested using microsatellite markers.
Twelve species were identified from S. birrea and eleven species were found on M. indica
trees. From isolations done in 2006, the dominant species on S. birrea was
Neofusicoccum vitifusiforme, while N. parvum was the dominant species isolated from M.
indica. Neofusicoccum parvum was dominant in isolations from both hosts in 2012.
Isolates of Botryosphaeria fabicerciana, Lasiodiplodia mahajangana, L.
pseudotheobromae, L. theobromae, N. mediterraneum and N. umdonicola were also
collected from both hosts. Population genetic analyses on isolates of N. parvum suggested
that three populations were present, each comprising isolates from both hosts. There was
significant gene flow between N. parvum populations on these hosts. This ability to infect
multiple hosts and to migrate amongst them facilitates the establishment and spread of
species and genotypes of the Botryosphaeriaceae, such as N. parvum, in new areas.
