Fusariotoxins in asparagus – their biosynthesis and migration

Abstract

Asparagus is often infected by fungi of the Fusarium genus, a causal agent of crown and root rot, which decreases the quantity and quality of spears. Fusarium oxysporum and Fusarium proliferatum are the most severe asparagus pathogens, well known as mycotoxin producers, mainly fumonisins and moniliformin. The present study was undertaken to estimate fumonisin B₁, moniliformin and ergosterol concentrations in asparagus tissue. Moreover, the possibility of toxin transport to the edible asparagus part during the inoculation by F. oxysporum and F. proliferatum of different plant parts (root, crown and stem base) and the potential risk for consumers were assessed. Our studies showed that the highest capability of producing fumonisin B₁ and moniliformin was demonstrated from isolates of F. proliferatum. The highest level of fumonisin B₁ in edible spears was detected when the asparagus crown was inoculated with F. oxysporum and F. proliferatum. The lowest concentration was found in the case of storage root inoculation, which corresponds with mycelium absence and the long distance from the roots to the stem. Similar results were demonstrated for moniliformin. The mycotoxin content was confirmed even in healthy spears (without disease symptoms and mycelium presence), which might indicate that the transport of mycotoxins is possible from the soil through the root system to the top part of the plants.

Keywords:

• asparagus spears
• Fusarium oxysporum
• Fusarium proliferatum
• HPLC
• fumonisins
• moniliformin
• ergosterol

Acknowledgement

This study was partly supported by the Ministry of Science and Higher Education of Poland (Projects Number NN 3101709 33 and NN 312 0747 40).