3. Results
3.1. Effects of T. harzianum T22 seed treatment on F. verticillioides
colonization and fumonisin contamination in kernels
F. verticillioides infection and fumonisin content in maize kernels
were evaluated after T. harzianum seed treatment. T. harzianum
treatment reduced the amount of F. verticillioides kernel colonization
by 32% and 85% (three-year average) at Rovigo and Cremona,
respectively. The reduction in the fungal content was significant
(P < 0.01) at Cremona during each growing season from 2006 to
2008, while at Rovigo the reduction was significant (P < 0.01) only
for the years 2006 and 2008 (Table 2).
In the experimental trials we considered the influence of treatment,
site and year as factors affecting F. verticillioides content in
kernels. Statistical analysis revealed that F. verticillioides colonization
was significantly reduced upon T. harzianum treatment compared
with untreated plants (P < 0.0001), with each factor analyzed
separately and in interaction with the other factors (Table 3).
In addition to fungal quantification in kernels, T. harzianum
treatment induced a significant decrease (P < 0.05) of fumonisin