Location: Crop Improvement and Genetics Research
Project Number: 2030-21220-003-025-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2025
End Date: Aug 31, 2026
Objective:
The proposed research will pursue a collaborative project investigating the grapevine smoke-responsive transcriptome and metabolome. The two datasets will be integrated to provide a better understanding of the physiological changes that occur in grapes in response to smoke exposure.
Objective 1: Grapevine transcriptome and metabolome responses to smoke exposures pre- and post-veraison in both leaves and fruit will be evaluated. This will include samples collected both during and after the smoke exposure to evaluate the acute response as well as the response post-exposure. Replicate samples of fruit and leaves within a single smoke house, as well as between houses will be collected during the post-veraison smoke exposure trials to evaluate and compare the consistency of smoke exposure within and between smoke houses.
Objective 2: Smoke exposure trials will be performed with sample sets where shoots (leaves only), clusters only, both shoots and clusters and neither shoots nor clusters will be covered to selectively block smoke exposure. The gene expression results will be evaluated to determine the relative importance of the translocation of smoke related compounds from exposed tissues to nonexposed (protected) tissues.
Objective 3: Selected glycosyltransferases and potentially other candidate proteins will be expressed using bacterial or yeast expression systems and their ability to enzymatically convert substrate volatile compounds into glycosylated or other modified chemical forms will be evaluated.
Approach:
Smoke exposures will include pre- and post- veraison fruit and leaf samples from Merlot vines exposed in the vineyard and the evaluation of the gene expression and metabolomic responses that occur during and after the smoke exposure ends. This effort includes field work conducting the smoke exposure in houses in the vineyard, the collection of fruit and leaf samples at a range of timepoints following smoke exposure, and lab work performing RNA isolation and metabolomic analyses. The relative importance of the exposure of the leaves versus the fruit will be evaluated and the impact that the potential translocation of the volatiles and their glycosylated forms have on developing berries examined. The ability to deliver consistent levels of smoke to each of the smoke houses has been previously impacted by wind and potentially other environmental factors during the 36-hour exposure periods. Additional experimental sampling will be performed within individual smoke houses (with a presumed more uniform smoke exposure) to provide additional biological replication and to control for the environmental differences that may occur between separate smoke houses. Completion of Objectives 1 and 2 will provide additional biological replicated results supporting the publication of the grapevine smoke responsive transcriptome. Objective 3 will pursue in vitro enzyme activity studies of glycosyltransferases and other candidate proteins to investigate their enzymatic role in the modification and retention of the smoke-derived volatile compounds within grapevine fruit tissues.