Abstract:
Botryosphaeriaceae represents a diverse family of fungi with a cosmopolitan distribution
and a wide host range. We studied species diversity and overlap of Botryosphaeriaceae on selected
tree species of Anacardiaceae in disturbed (farming or forestry) and undisturbed (isolated and/or
protected) ecosystems in the Limpopo and Mpumalanga provinces, South Africa. The disturbed sites
resided at Tshikundamalema and Tshipise in Limpopo and the undisturbed sites at Nwanedi and the
Mapungubwe National Park in Limpopo and the Kruger National Park in Mpumalanga. Asymptomatic branches were collected from Mangifera indica, Sclerocarya birrea and Lannea schweinfurthii trees
in 2017 and 2018. Eleven species were identified using a multi-gene sequencing approach, including
Diplodia allocellula, Dothiorella brevicollis, Do. dulcispinae, Do. viticola, Lasiodiplodia crassispora, L. exigua,
L. gonubiensis, L. mahajangana, Neofusicoccum parvum, Oblongocollomyces sp. 1 and Oblongocollomyces sp.
2. Ten of the 11 species were identified in undisturbed ecosystems (eight species being unique), while
only three species were identified in disturbed ecosystems (one species being unique). Two species
were generalists on trees in disturbed and undisturbed ecosystems. Lasiodiplodia mahajangana was the
most dominant species as it occurred on the three tree species of Anacardiaceae. Isolates of N. parvum
occurred on both S. birrea (a native species) and M. indica (a non-native species) that occurred adjacent
to each other in disturbed ecosystems, confirming the ability of this invasive pathogen to cross-infect
native and non-native hosts and its abundance in human-disturbed environments. The findings from
this study confirm the lack of host specificity for most species of Botryosphaeriaceae. The results also
indicate that disturbance through human activity, such as clear-cutting, selective cutting and land-use
changes, negatively influences the diversity of the Botryosphaeriaceae.
Description:
Supplementary Materials: Figure S1: Genealogical concordance phylogenetic species recognition (GCPSR)
based on analyses of the ITS, tef-1α, β-tub and rpb2 sequence data. Bootstrap values above 70% and
PP values above 0.95 are shown at the nodes. Isolates in bold were obtained in this study. The trees
are rooted to isolates of Melanops tulasnei (CBS116805, CBS116806).