Diagnosis of pathogenic fungus causing dimple rot on Gold3 kiwifruits in Jej u Island

Abstract

Since the past few years dimple rot has been one of the most serious diseases affecting Actinidia chinensis var. chinensis Gold3 kiwifruit in Korea, which causes low quality of production and consequently losses of income. In the current study, the causal pathogen of dimple rot on Gold3 kiwifruit was identified as Botryosphaeria dothidea, a widespread pathogen which is able to penetrate the fruit directly without wounding. Correspondingly, pathogenicity of the fungus was evaluated on other kiwifruit cultivars such as Hayward and Hort16A. Among the other two cultivars, Gold3 was the most susceptible one to infection. Since dimple-rot symptoms have been previously associated with other pathogens from the Pseudocercospora genus, in this study B. dothidea was ratified as the causal agent of this disease in Jeju Island. To illustrate the high pathogenicity of the fungus on Gold3, further studies such as the observation of the infection structures of the fungus may be needed.