Table 1, at 1.2 mg/ml neither epicatechin
nor catechin affected conidial germination
and appressorial formation of C. kahawae Z1; at
2.3 mg/ml both of them slightly and significantly
inhibited conidial germination but did not affect
appressorial formation. However, at both these
concentrations, epicatechin and catechin both
significantly inhibited conidial germination and
appressorial formation of C. gloeosporioides
Ch27.
These results indicate that the non-pathogen
C. gloeosporioides was more sensitive to epicatechin
and catechin. Moreover, the appressorial
melanization of both isolates was totally inhibited
by epicatechin or catechin, reducing the percentage
of appressorial melanization from nearly
100% of the control to zero. These results indicate
that both epicatechin and catechin significantly
inhibited melanin biosynthesis of the appressoria
of C. kahawae and C. gloeosporioides. In addition,
there was no significant difference between epicatechin
and catechin on conidial germination and
appressorial formation and melanization of
C. kahawae and C. gloeosporioides.