Postharvest apple rot causes severe economic losses and lowers apple quality, and is one of the most important limiting factors of apple exports. Apples with rot symptoms were sampled from Geochang, South Korea. Isolation of the causal fungus was performed by culturing small pieces of diseased tissues on potato dextrose agar. Two different rot genera, Fusarium and Alternaria, were identified according to their morphological characteristics. To confirm the identity of the causal fungus, we sequenced the DNA of the complete internal transcribed spacer(ITS) rDNA gene region and translation elongation factor 1-alpha(EF1-α) region. Koch’s postulates were supported by pathogenicity tests conducted on apple fruit. Based on mycological characteristics, molecular identification, and pathogenicity tests, the two fungi were identified as Fusarium tricinctum and Alternaria alternata. To the best of our knowledge, this is the first report of postharvest apple rot caused by F. tricinctum and A. alternata in South Korea.
고추의 뿌리에 서식하고 있는 근권미생물을 30여종 분리하여 고추 검은 곰팡이병원균 A. alteranta에 길항하는 미생물을 분리한 결과 분리주 No. J-24 균주가 가장 길항력이 우수하였으며 Bacillus subtilis로 동정되었다. B. subtilis J-24는 검은곰팡이병균(Alternaria alternata)에 대해서는 생육저지 효과가 99%로 나타났으며, 그외 갯빛곰팡이병균(Botrytis cinerea), 역병균(Phytophthora capsici), 잘록병균(Pythium ultimum), 탄저병균(Colletotrichum gloeosporioides), 겹무늬병균(Stemphylium botryosum)에도 생육저지효과를 강하게 나타내었다. 고추 유묘의 생장활력은 미생물제제가 첨가된 상토가 일반 상토 보다 엽면적이 15%, 줄기길이가 12%, 뿌리길이가 12% 증가하였고 전체 건물중이 약 13% 증가하여 고추유묘의 생장활력이 증가되었다.
Effect of some physical and chemical factors on germination of conidia of Alternaria alternata (Fries) Keissler causing fruit rot of apple was investigated. The germination was maximum at , 100 per cent RH and at 5.5 pH Syllit, amongst the 11 fungicides and Planofix, amongst the 5 growth regulators caused maximum inhibition of conidial germination.