Lasiodiplodia gonubiensis sp. nov., a new Botryosphaeria anamorph from native Syzygium cordatum in South Africa

Abstract

Botryosphaeria spp. are common and widely distributed pathogens on many economically important crops, includ- ing forest tree species. These fungi cause a wide variety of symptoms on trees of all ages, but are mostly associated with canker and die-back of branches and main stems. As disease agents, Botryosphaeria spp. are often encountered in their anamorph state, namely species of Fusicoccum, Diplodia or Lasiodiplodia. During a recent survey of botryosphaeriaceous fungi from native Syzygium cordatum in South Africa, an unfamiliar Lasiodiplodia sp. was isolated. The aim of this study was to compare this apparently undescribed species with other species of Botryosphaeria using morphological characteristics and DNA sequence data of the rDNA internal transcribed spacers, ITS1 and ITS2. Based on sequence data, the isolates from S. cordatum were more closely related to B. rhodina (anamorph Lasiodiplodia theobromae) than to other Botryosphaeria spp., but also phylogenetically distinct from this species. Conidia of the species from S. cordatum were also different to those of L. theobromae. We conclude that the isolates from S. cordatum represent an undescribed Lasiodiplodia sp. and provide the name Lasiodiplodia gonubiensis for it.