Fusarium proliferatum occourence and fumonisins accumulation risk on garlic food chain.

Fusarium proliferatum is an emerging, spreading worldwide pathogen of garlic, causing bulb rot. During the whole crop cycle, fungal presence is not associated to characteristic symptoms. During storage, infected bulbs, conversely, undergo to a slow deterioration process: at first brown depressed water soaked spots and, in extremely severe infections, the entire bulbs rot, reducing the garlic shelf-life. The disease leads to appreciable loss of product. This fungus is well known to produce fumonisins. White garlics, cultivated in different northern Italian regions are subjected to mycological and HPLC analysis, to detect the pathogen and quantify the mycotoxins. Basal plate of garlics were dissected and cultured in PDA Petri dishes amended with streptomycin and neomicyn sulphate. Strains morphologically belonging to F. proliferatum species were tested by PCR with specific primers and with primers for Fum1 gene involved in fumonisin production. For mycotoxin analysis, cloves were dried for one week at 40°C, grinded in fine powder and analyzed by IAC/HPLC. F. proliferatum is present in all the tested bulbs and all the strains collected show the presence of FUM1 gene. The Fumonisin levels in cloves ranged from 0,05 ppm to 0.68 ppm for B1 and up to 0.1 for B2. These quite low levels are reached within a short period of conservation in comparison to the time from storage to consumption. Mycotoxin levels should be checked in different food chain steps and on garlic derived products, therefore it is necessary to consider the influence of the conservation time at home, by consumers to better evaluate the possible risk in human health