Cellulolytic enzymes associated with the fruit rots of Citrus sinensis caused by Aspergillus aculeatus and Botryodiplodia theobromae

Botryodiplodia theobromae and Aspergillus aculeatus were inoculated on carboxymethylcellulose (CMC) medium and filter papers. The hydrolysis of the CMC medium and degradation of the filter papers were observed, indicating the production of the C_l and C_x cellulases by the two rot pathogens. The C_l and C_x enzymes were also detected in filtrates of rotted orange fruits incited by the two rot pathogens.The cellulases could not induce rot development on their own. However, when they were added to pectinases in an enzyme inoculum, the incubation period for inducing rot development was shorter; thus establishing a secondary role for the cellulases in the rot development. This secondary role of the cellulases produced by the two fungi was found to be at peak at pH 7 and a temperature range of 25°–30 °C in the two fungi.