The microbiology of South African wine making. Part VIII. The microflora of healthy and Botrytis cinerea infected grapes

In order to assess the possible cause of the low quality of some wines made from Botrytis infected grapes, a survey was carried out to determine whether certain undesirable micro-organisms are associated with Botrytis cinerea infection of grapes. The yeast species, Torulopsis bacillaris, Candida krusei and Kloeckera apiculata appeared to be associated with B. cinerea. B. cinerea seemed to inhibit Rhodotorula glutinis since it was seldohn isolated from Botrytis infected grapes. The results also indicate an inhibitory action of B. cinerea upon certain fungi; the effect is particularly noticeable on the genus Aureobasidium, Cladosporium herbarum, Alternaria tenuis and Fusarium solani. Aspergillus species, however, were numerous on Botrytis infected grapes. Acetic acid bacteria were numerous on Botrytis infected grapes, but rare on healthy grapes. No relationship was found between B. cinerea infection and the presence of lactic acid bacteria