Erysiphe abeliicola에 의한 꽃댕강나무 흰가루병 발생

Abstract

In November 2009, a powdery mildew on glossy abelia (Abelia x grandiflora) was found in Seogwipo, Jeju Island, Korea. Further survey in the southern part of Korea, e.g., Jeju, Busan, and Tongyeong confirmed occurrence of the disease. White colonies were present on leaves, young stems, and flowers, detracting from their beauty in landscape plantings. Severely infected lesions were discolored to red-purplish. Based on the morphological characteristics and analysis of rDNA, the fungus associated with the symptoms was identified as Erysiphe abeliicola U. Braun & S. Takam. This work provides the morphological feature of its anamorph for the first time, which is characterized by having multi-lobed hyphal appressoria and short foot-cells of conidiophores. Morphological characteristics of mature chasmothecia were consistent with the previous Japanese record of this species. The sequence of internal transcribed spacer region of ribosomal DNA obtained from a Korean sample showed that this species places in the section Microsphaera of the genus Erysiphe in phylogenetic position, corresponding with the classical taxonomy. This is the first report of E. abeliicola and its host plant in Korea. The host plant A. x grandiflora is newly listed in the host range of E. abeliicola.