Abstract:

Isolation and identification of pathogens from the decayed tissues of melon stored in winter were carried out using LB (lysogeny broth) and PDA (potato dextrose agar) media. Based on morphological characteristics, D1/D2 region of 26S rRNA sequences for fungi, 16S rRNA gene sequences for bacteria and phylogenetic trees, a total of 22 strains were isolated. Thirteen of them belonged to the family of fungi, including 2 strains of the genus Penicillium, 4 strains of the genus Alternaria, 4 strains of the genus Geotrichum, and 3 yeast strains (2 strains of the genus Metschnikowia and 1 strain of the genus Pichia); the rest were all bacteria, including 5 strains of Serratia. sp, 1 strain of cloves. sp, 1 strain of Klebsiella. sp, 1 strain of Enterobacter. sp and 1 strain of Bacillus. sp. The results of 26S rRNA and phylogenetic tree analysis revealed that 2 isolates (strain 121 and strain 122) were yeast, which may be a new species belonging to the genus Metschnikowia. Alternaria and Penicillium were pathogenic fungi for melon, and Geotrichum and Serratia. sp were pathogens for human. Therefore, these investigations demonstrate that current conditions for winter storage of melon should be improved.

Key words: decayed melon, winter storage, pathogens, isolation, identification, 16S rRNA, 26S rRNA