Aureobasidium pullulans is present in the majority of vine production areas in the world; it is found in many soils, on the most diverse plants and plant debris, as well as sometimes on seeds. It is probably part of the phylloflore of the vine found on the leaves, the fruits, in the bark, and sometimes in the weathered wood of vines affected by eutypiosis or esca for example.

It can be responsible for lesions and rots on many alternative hosts which thus help to multiply and conserve them.

 

This fungus does not seem to attack the grape berry. It has occasionally been associated with grape damage, but probably as a secondary invader given its high frequency in the vineyard and on mature berries. On the other hand, it has been widely tested as a biopesticide to control the development of various rotting agents in post-harvest.

Its parasitism on rounds is punctual, not serious, with poorly defined modalities of expression.

 

This yeast-like fungus sporulates quite easily on many substrates and thus on the surface of browned stems and its blastospores which are found suspended in the air are dispersed by air currents and / or splashing water following rains.

 

It grows quickly and sporulates profusely if the humidity level is high enough. It is able to develop at temperatures between 2 and 35 ° C, with a thermal optimum close to 30 ° C. Note that this fungus is able to survive in extreme conditions: high and low temperatures, extreme light, low humidity.