Hop-associated bacteria with growth-promoting traits and antifungal activities: a sustainable solution for Italian hop farms

Abstract: In Italy, hop cultivation and pest management are still challenging. Nevertheless, the exploitation of the hop-associated microbiome offers a promising solution to identify possible beneficial microorganisms. In 2023 and 2024, root-associated bacteria were isolated from both hop wild accessions and commercial cv. Cascade orchards in Modena and Perugia provinces (Italy), respectively. Among a set of 263 isolates, the seven best performing bacterial isolates were selected, based on their antagonistic activities against Verticillium dahliae and Botrytis cinerea and plant growth promotion traits. Our findings propose a set of promising biocontrol bacterial isolates, belonging to the genera Pseudomonas, Pantoea and Burkholderia, for the development of alternative and sustainable strategies to control hop fungal diseases.