Ripe rot caused by Botryosphaeria dothidea is one of the serious diseases of postharvest kiwifruit. In or-der to control ripe rot on Actinidia chinensis cultivar ‘Zesy002’, several commercial agrofungicides were selected by an antifungal test on an artificial medium. Furthermore, disease suppression by the selected fungicides was evaluated on the kiwifruit by inoculation with a conidial suspension of B. dothidea. On the artificial media containing boscalid + fludioxonil was shown to be the most effective antifungal activity. However, in the bio-test pyraclostrobin + boscalid and iminoctadine-tris were the most effective agrochemicals on the fruit. On the other hand, the infection structures of B. dothi-dea on kiwifruit treated with pyraclostrobin + boscalid were observed with a fluorescent microscope. Most of the fungal conidia had not germinated on the kiwifruit treated with the agrochemicals whereas on the un-treated fruit the fungal conidia had mostly germinated. Electron microscopy of the fine structures showed morphological changes to the conidia and branch of hyphae on the kiwifruit pre-treated with pyraclostrobin + boscalid, indicating its suppression effect on fungal growth. Based on this observation, it is suggested that ripe rot by B. dothidea may be suppressed through the inhibition of conidial germination on the kiwifruit treated with the agrochemicals.
Bibliographical noteFunding Information:
This work was supported by Zespri Group Limited, New Zealand through a research and development service program and a research grant of Jeju National University in 2021.
© The Korean Society of Plant Pathology.
- Dimple rot
- Fluorescence microscopy
- Infection structure
- Plant protection
- Postharvest disease
ASJC Scopus subject areas
- Agronomy and Crop Science