Ms. Tial Len Sung

Sour rot is a disease affecting grape berries and characterized by rot, pulp liquefaction and smell of vinegar (acetic acid). The disease develops through an interaction between grape berries, yeast and acetic acid bacteria (AAB) and Drosophila flies. Infested grapes are often not harvested or are removed during pos-tharvest sorting because they are not suitable for fresh consumption or risk producing wine with unacceptable levels of total and volatile acidity. Previous studies have shown that sour rot does not occur in the absence of flies and their associated yeast and bacteria. I study the interaction between Drosophila flies and their microbiome in relation to fruit characteristics and the agricultural context. I hypothesize that the microbiome has a significant impact on larval development by affecting nutrition and possibly through detoxifying insecticides. By removing the maternal microbiome from the eggs and comparing larval development between apo-symbiotic (microbe-free) and symbiotic counterparts, I demonstrate that development is microbiome-dependent. I am currently examining the detoxification potential of the microbiome during larval development – specifically how the microbiome contributes to larval tolerance to plant defense compounds and insecticides. I expect to find that the symbiont microbes will help the larva to overcome nutritional deficiency in the grape berries and possibly detoxify xenobiotic compounds during their development and that this host-microbe interactions may provide information useful for Drosophila pest control in the vineyards.