Diplodia scrobiculata found in the southern hemisphere

Abstract

Diplodia scrobiculata, a latent pathogen of Pinus spp. and other conifers with a limited distribution in the United States, Mexico and southern Europe, has not been reported previously in the southern hemisphere. This is unlike its close relative Diplodia pinea that is found in most parts of the world where pines are native or have been introduced. During an intensive D. pinea survey conducted in Pinus patula plantations in eastern parts of South Africa, a small number of isolates atypical of D. pinea were found. Morphological studies and DNA sequence comparisons showed that these isolates represent D. scrobiculata. Microsatellite analyses suggest that the South African isolates of D. scrobiculata might have originated from California. Pathogenicity tests showed that some of the D. scrobiculata isolates were as pathogenic as those of D. pinea on Pinus radiata and Pinus elliottii.