NEW TOXIGENIC PENICILLIUM SPECIES ASSOCIATED WITH APPLE BLUE MOLD IN SAUDI ARABIA

摘要

Two apple blue molding Penicellium species; Penicillium asperosporum (G. Smith) and Penicillium puberulum (Bain) were isolated for the first time in Saudi Arabia. Macro and micro morphological features along with mycotoxin productivity and pathogenic behavior were significant in characterization of these fungi. Mycotoxin productivity revealed that citrinin and patulin were produced by both fungal species but penicillic acid (1.6 ppm) was only produced by P. puberulum. Moreover, P. asperosporum could produce more patulin (6.65 ppm.) and less citrinin (4.86 ppm) than P. puberulum. Inoculation of artificially wounded apple fruits with conidial suspension resulted in typically blue mold symptoms. P. puberulum was more aggressive on Fuji and red delicious but less on green apple fruits comparing with P. asperosporum. Lesion diameters induced by P. puberulum (19.25 &11.60 mm) were larger than those by P. asperosporum (18.60 & 6.50 mm) on Fuji and red delicious apple fruits respectively.