국내 사과그을음점무늬병균 Peltaster fructicola 및 Schizothyrium spp.에 대한 살균제의 균사 생장 억제 효과 검정

다국어 초록 (Multilingual Abstract)

In 2023 and 2024, we collected 77 apples showing symptoms of flyspeck from orchards in Gangwon, Gyeongbuk, and Jeonbuk provinces, Korea. We isolated a total of 52 fungal strains from symptomatic fruits and based on cultural characteristics and phylogenetic analyses, they were identified as Peltaster fructicola, Schizothyrium wisconsinense, S. pomi, and S. emperorae. Fifteen strains were isolated from the punctate type and identified as Peltaster fructicola. We isolated 37 strains of the flyspeck type, among which the predominant species were Schizothyrium wisconsinense (18 strains) and S. pomi (12 strains). Since no fungicides are currently registered specifically to control flyspeck in apples in Korea, there are limited studies on effective fungicides against these pathogens. Using fungicide-amended media, we evaluated the efficacy of 17 fungicides registered for use on apples. The fungicides targeted 13 strains representing three predominant species, P. fructicola, S. wisconsinense, S. pomi. Our results showed that tebuconazole WP, mefentrifluconazole WG, and metconazole SC in the G1 group, benomyl WP in the B1 group, and mancozeb WP in the M group exhibited over 80% of mycelial growth inhibition rates in all the tested strains. Although the inhibition rates against most strains were above 80%, group C2 that consists of fluxapyroxad SC, penthiopyrad SC, and pyraziflumid SC showed inhibition rates of 60~80% against some strains. In contrast, fungicides in the C3 group generally showed mycelial growth inhibition rates of less than 60% in most strains. Our results represent the first report on the isolation frequency of flyspeck pathogens in apples and provide a basis to establish effective management strategies for flyspeck in apples in Korea.