Objective 3

The focus of activity 3.1. is consumer panel testing of Abies Christmas tree species.

The Objective 3 team plans to perform sensory tests to evaluate consumer preferences for aroma profiles of fir species, individual families within species, and individual terpene metabolites. Consumers prescreened as having purchased a live Christmas tree in within the previous three years will be given sensory tests that cover odor intensity and acceptability. These tests will use small branch segments collected at a normal annual harvest window during the Christmas holiday season. An addition to the sensory screening, consumers will be given a follow-up questionnaire to gauge opinions of Christmas tree aromas and appearances, as well as level of acceptance towards genetically improved Christmas trees. Questions for these surveys will be developed in consultation with Extension Specialists and the IMPACT advisory board.

The main focus of Activity 3.2. is to evaluate post-harvest changes to fir Christmas tree aromatic profiles over time.

The Objective 3 team plans to evaluate post-harvest changes in aromatic profiles and identify compounds that associate with a negative response from consumers over time. Terpene profiles of Fraser, noble, and CoFirGE complex species will be evaluated after harvest over an eight-week period. Branches will be harvested from a single genotype for each species of interest every two weeks starting October 1st and ending November 30th to correspond with harvest season, a baseline sample will be evaluated at each time-point, and branches will be displayed in such a way that emulates consumer trends for Christmas tree display and use. At the end of the display period, aroma profiles will be compared to identify differences amongst harvest windows.

The main focus of Activity 3.3. is determining if terpene compounds that repel deer and/or attract humans are overlapping or different profiles.

It is not currently known if the terpene profiles that repel deer are aligned with preferred consumer aromas. In order to learn more about this component of Christmas tree aroma, the Objective 3 team will compare the relationship between species, genotypes, and metabolites that deter deer and/or are preferred by humans. Terpene metabolites that correlate with deer browse deterrence will be utilized in the consumer sensory tests given as part of Activity 3.1. to evaluate human aroma preference. Any terpenes that correlate with deer browse deterrence and are preferred by consumers will be prioritized for gene discovery purposes.

The main focus of Activity 3.4. is aroma compound gene discovery and exploration of potential alternative income streams for Abies spp. Christmas tree waste products.

The objective 3 team will do this by first identifying terpene-biosynthetic pathway networks in commercial Abies species (Sub-Activity 3.4.1.) and functionally characterizing key terpene-metabolic genes (Sub-Activity 3.4.2.). With this information, the Objective 3 team will work to develop a sustainable, cost-effective platform for extracting high-value terpene compounds from Christmas tree waste material (Sub-Activity 3.4.3.). There is at least one known, high valuable terpene metabolite produced by fir that could be a usable waste material from Christmas trees. Due to its natural aroma-producing chemistry, this terpene, cis-abienol, could be used to produce base notes in the fragrance industry. To investigate this use of terpene further, the Objective 3 team will carry out extraction and analyses of terpenes to evaluate quantity of cis-abienol present in Fraser fir waste materials.

The main focus of Activity 3.5. is understanding public and consumer perceptions of genetic improvement in Christmas trees.

There is little known about general public and consumer perceptions of genetic interventions for Christmas trees. By understanding public perceptions regarding the use of genetic tools to improve Christmas trees, the Objective 3 team will be able to explore the public/consumer perceptions of tree improvement (for traits like climate resilience, needle retention, and aroma) and underlying value systems that shape perceptions about Christmas trees. The objective 3 team plans to conduct four focus groups (of 8-10 people each) comprised of potential consumers, who will be questioned about genetic improvements of Christmas trees. Focus group responses will allow for evaluation of how genetic improvement and the positive benefits associated such as potential price reductions for real trees and better climate practices impact the debate for artificial versus real trees.