Phlyctema vagabunda is the main causal agent of apple bull’s eye rot in New Zealand

Abstract

AbstractBull’s eye rot is a postharvest storage disease of apples. Until now the cause of this disease in New Zealand was not clear. A survey of 6880 apples from five regions of New Zealand over two seasons was conducted. Neofabraea malicorticis and N. perennans were not found. One hundred and seventy-nine isolates were identified as Phlyctema vagabunda by specific polymerase chain reactions and/or sequencing the β-tubulin gene region followed by phylogenetic analysis. Two isolates were identified as N. kienholzii. Previous records of the presence of N. malicorticis and N. perennans in New Zealand were based on spore morphology and presence in pruning wound cankers. There is overlap in spore morphology for N. malicorticis, N. perennans and P. vagabunda, accounting for misidentifications. Based on our results it is likely that previous records were P. vagabunda, which can also infect pruning wounds.