P-508 - Insects as potential vectors of grape sour rot: ecological insights into microbial dynamics.

Grape sour rot is a complex caused by the interaction of microbes and insects, specifically Drosophila melanogaster. Sour rot is exacerbated in physically injured berries in the presence of D. melanogaster. It is an important disease in grape production, yet the microbial patterns associated with it and the role of insects as potential vectors remain poorly understood. The goal of this study is to investigate fungal and bacterial communities associated with sour rot during veraison and pre-harvest stages on both grapes and insects. Specifically, we will identify microbial taxa in insects that correlate with those found on grapes, investigate temporal changes, and evaluate the potential of  insects visiting berries as vectors for microbial communities associated with sour rot. Grapes and insect samples were collected from a Vignoles vineyards susceptible to sour rot at both veraison and pre-harvest stages. DNA was extracted from insect and grape samples and subjected to 16S rRNA and ITS amplicon sequencing to profile bacterial and fungal communities. Microbial composition and diversity of grapes and insects will be analyzed using alpha and beta diversity indices. We will conduct correlation analysis to assess the relationship between insect and grape microbial communities, and differential abundance analysis to evaluate if insect-associated taxa increase on grapes during harvest stage. This study provides insights into sour rot ecology through knowledge of microbial dynamics in grapes and the potential of insects as vectors, guiding more effective management strategies.