Differential reactions on mature green and ripe chili fruit of 10 genotypes from four
cultivated Capsicum spp. (i.e., Capsicum annuum, C. baccatum, C. chinense, and C.
frutescens) were investigated after being inoculated with 33 isolates of Colletotrichum
capsici, C. gloeosporioides, and C. acutatum originating from Thailand. The inoculation
was performed using an injection method. Differential reactions, based on qualitative
host reactions (i.e., lesion development versus no infection) grouped the Colletotrichum
isolates into different pathotypes. C. capsici was grouped into three pathotypes based
on differential reactions on ripe fruit stage of two Capsicum chinense genotypes (PBC932
and C04714) and two pathotypes based on differential reactions on mature green fruit
stage of C04714. Colletotrichum gloeosporioides was grouped into five and six pathotypes
on their reactions in ripe and green fruit maturity stages, respectively. C04714 and
two Capsicum annuum genotypes (Jinda and Bangchang) acted as differential hosts with
ripe fruit, whereas C04714 with all C. annuum and C. frutescens genotypes acted as
differential hosts with green fruit. No pathotype of Colletotrichum acutatum was identified
on ripe fruit but three pathotypes were identified on green fruit based on differential
reactions in two Capsicum baccatum genotypes (PBC80 and PBC81).