
Suppression of Melanose Caused by Diaporthe citri on Citrus Leaves Pretreated with Bio-sulfur
- Yong Ho Shin Eun Ju Ko Su Jeong Kim He Nam Hyun Yong Chull Jeun
- 한국식물병리학회
- The Plant Pathology Journal
- 제35권 제5호
- 등재여부 : KCI등재
- 2019.10
- 417 - 424 (8 pages)
Melanose, caused by Diaporthe citri, is one of severe diseases in citrus, a major economic resource in Jeju island. To reduce the usage amount of organic synthetic fungicide, bio-sulfur was tested as an alternative chemical to control citrus melanose in the present study. Direct antifungal activity of bio-sulfur against D. citri was determined through in vitro experiment using artificial nutrient media. Disease severity of melanose on bio-sulfur pretreated citrus leaves was lower than that on untreated ones. To illustrate the mechanism of disease suppression by bio-sulfur, infection structures were observed with a fluorescent microscope and a scanning electron microscope. In fluorescent microscopic observation, most conidia rarely germinated. In addition, hyphal growth on leaves pretreated with biosulfur was inhibited compared to that on untreated ones. In scanning electron microscope images of biosulfur pretreated leaves, surfaces of most conidia were shrunk while hyphae were morphologically changed and frequently branched. Such microscopic observations were also found for leaves pretreated with a commercial fungicide Dithianon. These results suggest that bio-sulfur may be used to control citrus melanose as an environment friendly alternative to organic synthetic fungicides
Material and Methods
Results and Discussion