MOLECULAR DETECTION OF FUSARIUM VERTICILLIOIDES, F. PROLIFERATUM AND F. SUBGLUTINANS USING POLYMERASE CHAIN REACTION

Fusarium verticillioides, F. proliferatum and F. subglutinans, the aetiological agents of corn ear rots, are morphologically very similar, but differ for their toxigenic capabilities. In fact, only F. verticillioides and F. proliferatum are strong fumonisin producers. Therefore a reliable and rapid method is required to detect and distinguish these three species in maize kernels. Four different primer pairs, namely VER1/2 and VERTF1/2 species-specific for F. verticillioides, PRO1/2 for F. proliferatum and SUB1/2 for F. subglutinans, were tested on several strains belonging to 16 well known Fusarium species commonly associated with corn. VER1/2 and VERTF1/2 detected not only F. verticillioides but also F. nygamai and F. napiforme. Moreoever VER1/2 amplified the target DNA of F. equiseti. PRO1/2 was strictly species-specific for F. proliferatum. SUB1/2 detected both F. subglutinans and F. nygamai. Molecular analysis carried out on corn samples naturally contaminated with F. verticillioides and/or F. proliferatum gave inconsistent results. Therefore, the proposed primer pairs were able to detect F. verticillioides, F. proliferatum and F. subglutinans but should be further optimized to be used as species-specific diagnostic tools especially where F. nygamai, F. napiforme and F. equiseti are likely to be found as corn contaminants.