Pectinolytic enzymes associated with the soft rots ofCitrus sinensis caused byAspergillus aculeatus andBotryodiplodia theobromae

Botryodiplodia theobromae andAspergillus aculeatus causing soft rots ofCitrus fruits were grown on wheat offal medium. The filtered washings of the wheat offal cultures were then assayed and found to contain pectinmethylesterases (PME) and polygalacturonases (PG). The two pectinases were also detected in large quantities from the filtrates of rotted fruits ofCitrus sinensis incited by each of the two test fungi. Two enzyme filtrates, one from rotted fruits ofCitrus sinensis and the other made up of pectinases from fungal cultures were introduced onto sterilised degreened fruits. Each of the two filtrates induced rot symptoms similar to those incited by the test fungi.Aspergillus aculeatus produced less PME and more PG thanBotryodiplodia theobromae.