Towards Biological Control of and in Grapevine Berries and Transcriptomic Changes of Genes Encoding Pathogenesis-Related (PR) Proteins.

Grapevine bunch rot, caused by and , causes important economic losses every year in grape production. In the present study, we examined the plant protective activity of the biological control agents, K165, sp. FP12 and sp. FP15 against and on grapes. The in vitro experiments showed that strain K165 significantly reduced the growth of both fungi, while FP15 restricted the growth of and FP12 was ineffective. Following the in vitro experiments, we conducted in planta experiments on grape berries. It was shown that K165, FP12 and FP15 reduced rot severity by 81%, 57% and 37%, respectively, compared to the control, whereas, in the case of , the only protective treatment was that with K165, which reduced rot by 75%. The transcriptomic analysis of the genes encoding the pathogenesis-related proteins PR2, PR3, PR4 and PR5 indicates the activation of multiple defense responses involved in the biocontrol activity of the examined biocontrol agents.