The pathogenic fungus Mucor
piriformis Fischer also causes postharvest rots on strawberries
as well as on several other fruit crops (Sholberg
1990). Pathogens may develop resistance towards
chemical fungicides, creating a need for even more
chemicals (Holmes and Eckert 1999). However, as
existing chemical fungicides may be harmful for mammals
and the environment, there is a need to reduce their
use. Attempts have been made to reduce gray mold
using biological or cultural control methods (Card
et al. 2009), but these often give less consistent results
than chemical control. There is a need for antifungal
products that cause no harm to the environment and are
non-toxic to mammals (Parvu et al. 2010). Chitosan
(deacetylated chitin) has long been known to have such
properties (Trotel-Aziz et al. 2006).