Location: Crop Improvement and Genetics Research
Project Number: 2030-21220-002-017-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2022
End Date: Aug 31, 2024
The proposed research is focused on determining the global gene expression profile of grapevine tissues, particularly developing fruit when exposed to wildfire smoke. Objective 1: Using leaves and fruit collected during ongoing smoke exposure trials, evaluate differences in the RNA transcriptome and berry/leaf metabolome between smoke exposed and control samples. Objective 2: Using samples collected at regular intervals during a smoke exposure trial, evaluate vine response to moderate intensity smoke over a 36-hour period as expressed in changes in the RNA transcriptome and the metabolome throughout the exposure period. Objective 3: Using techniques developed in Objectives 1 & 2, evaluate differences in vine response to smoke exposure pre- and post-veraison as expressed in changes in the RNA transcriptome and metabolome in leaves and fruit throughout the exposure period. Objective 4: Extend the trials described in Objectives 2 & 3 to include sampling and analysis of samples collected after the smoke exposure has ended to evaluate how the vine responds after the exposure has ended. Objective 5: During a smoke exposure trial as described in Objective 4, cover a random subset of clusters with bags that exclude smoke from reaching those clusters, to evaluate the relative importance of translocation of smoke related glycosides from smoke exposed leaves to the fruit and direct exposure/glycosylation in the fruit itself.
Field grown grapevines (Merlot, Cabernet Sauvignon, and Chardonnay, and potentially other cultivars) will be exposed to controlled amounts of smoke at a field site near Richland, Washington. The smoke exposure will be conducted in 3 modular portable hoop-houses, each which covers 30 vines in the field with 3 additional units used as non-smoke exposed control houses. All houses are covered with 80/20 shade cloth, which contains the smoke, while keeping the temperature inside the houses within a few degrees of the ambient temperature during the day. Smoke exposures will be for 36 hours in duration using side-firebox smokers, one for each hoop house. Hardwood pellets or other plant materials will be used to generate smoke. A PM1.0 particle counter will be used in each house to record the smoke density over the duration of the exposure. Active air samplers collecting smoke for their content of smoke-related volatile phenols will also be used to quantify the exposures. Eight clusters of berries will be collected for each timepoint (0, 2, 4, 8, 12, 24 and 36 hours) following smoke exposure, ensuring that sample collection for both the smoke-exposed and the control samples are completed with approximately 20 minutes. The samples will be kept in coolers with dry ice until they are transferred to -80C freezers for longer-term storage. RNA will be isolated from each of the berry skin and berry pulp samples and RNA-seq assays will be performed to acquire the global transcriptomic data. Special attention will be made from post véraison to harvest fruit samples, when the sensitivity to smoke exposure is the highest. The RNAseq data generated will analyzed and compared to publicly available transcriptomic studies on berry development in grapevine.