2.4. Measurements of mycelial growth
The mycelial disks (7 mm in diameter) from two-week-old cultures
of the fungi were placed in the centre of Petri dishes (60 mm
in diameter) with 10 ml solid PDA or PSA medium containing
different concentrations of chitosan or oligochitosan (0, 0. 1, 0. 3,
0. 5, 0. 7, 1.0 and 5.0 g/L), then incubated at 25 C. The mycelial
growth was determined by measuring colony diameter at 3 days
after inoculation, and the inhibitory rate of fungal growth and
hence the IC50 was calculated. Each treatment contained three replicates
and the experiment was repeated twice.