Characterization of a Brown Rot Fungus Isolated from Dwarf Flowering Almond in Korea

The fruits showing brown rot symptom on dwarf flowering almond were found in Gongju, Chungchungnam-Do in Korea in July 2005. Small water-soaked lesions on the fruits were initiated, and gradually developed to soft rot covered with gray conidia. Then the diseased fruits were shrunk and became grayish-black mummies. A fungus was isolated from the diseased fruit and its morphological, cultural and molecular genetic characteristics were investigated. Typical blastospores of Monilinia spp. were observed under a light microscope both from tissues of the diseased fruits and from PDA-grown cultures. The fungus grew well at 25degrees C and on PDA. The ITS ribosomal DNA region (650 bp) of the fungus was amplified by PCR and analyzed. Comparative data on ITS sequence homology among Monilinia spp., ITS sequence-based phylogram and morphological characteristics showed that the fungus is Monilinia fructicola. This is the first report on Monilinia fructicola causing brown rot on fruits of dwarf flowering almond in Korea.

Comparison of Characteristics of Ganoderma lucidum According to Geographical Origins (III): Classification between Species of Genus Ganoderma Using Dikaryon-Monokaryon Mating

A Monokaryotic strain G8M without clamp connections was isolated from germinated basidiospore that was obtained from cultivated fruit body. Strain G8M was used as a tester isolate for 'dikaryon-monokaryon mating' (di-mon mating) with the strains of Ganoderma lucidum, G6 and G35 (Korean wild strains), G3 (Taiwan), G4 (Canada), G15 (America), G. oregonense G24, G. resinaceum G28, G. oerstedii G23, and G. subamboinense G29. Isolate G8M was compatible to Korean strains G6 and G35, but was incompatible to foreign strains G3, G4, or G15. Compatible reactions between strains were readily observed macroscopically. Clear barrage lines formed between incompatible strains. These clear lines were not apparent in compatible di-mon matings. The Korean strains were morphologically distinct; they did not form any chlamydospores, and stopped growth at 35degrees C. The strains of G. lucidum from Korea may be considered as different species from Taiwan, Canadian and American cultures.