Diffusion of Patulin in the Flesh of Pears Inoculated with Four Post‐harvest Pathogens

The fungi Penicillium expansum , Aspergillus flavus , Stemphylium vesicarium and Alternaria alternata were experimentally inoculated into pear fruits of cv. Abate fetel. The infected fruits were split longitudinally through the centre of lesions (5, 10, 15 and 20 mm in diameter) and were divided into four sections, from tissues below the lesions to tissues around the carpel area. The aforementioned fungi were isolated in different frequencies from all sections that included diseased and healthy tissues. Patulin was detected in the flesh of pears with lesions 10 mm in diameter when inoculated with P. expansum , S. vesicarium and A. alternata , but not with A. flavus. Mycotoxin concentrations surpassed the accepted maximum residue limit in all sections, even in apparently sound tissues. This is the first report of invasion of these fungi, as well as patulin diffusion into different depths of pear fruits.