Location: Grape Genetics Research Unit (GGRU)
Project Number: 8060-21220-007-10-N
Project Type: Non-Funded Cooperative Agreement
Start Date: Oct 2, 2019
End Date: Jun 14, 2021
Characterization of fruit-set programs among diverse grape genotypes; evaluate the changes in hormones accumulation profile throughout fruit ontogeny; evaluate the changes in transcriptome profile among grape genotypes exhibiting differential fruit-set program; evaluate the function of genes associated with stenospermocarpy fruit-set using CRISPR/Cas9–gRNA ribonucleoproteins strategy; identify different proteins that are able to interact with TFs strongly associated with each type of fruit-set; evaluate the function of genes associated with stenospermocarpy fruit-set, using CRISPR/Cas9–gRNA ribonucleoproteins strategy; Develop training modules in grape genomics and biotechnology.
Different grapevine genotypes, including Vitis hybrids, V. vinifera and M. rotundifolia will be used for this study. The selected grape genotypes exhibit diverse fruit traits in terms of color, size, maturation date and mixed uses (table/wine), but have distinguishable fruit-set program, including seeded, stenospermocarpy seedless and parthenocarpy seedless. For each genotype, parallel fruit developmental stages from inflorescences until ripening will be collected and subjected to histological analysis by capturing cross-section images using microscope equipped with a digital camera, then all images will be imported into ImageJ software to quantify structural variables. The maturity stage will be determined via integrated measurements of pH levels and sugar/acid contents. At maturity, berries will be subjected to diverse evaluations in order to determine the degree of seedlessness. All fruit measurements will be recorded and converted into quantitative sub-trait components, including: number of days from inflorescences to ripening, berry weight, berry equatorial diameter, total number of seeds and/or seed traces, mean berry fresh and dry weight per seed or seed traces, and total seed or seed traces fresh and dry weight per berry. All the measurements will be presented as a mean value (3 plants/rep. X 5 replicates/genotype). Data from different genotypes will be subjected to standard statistical procedure tests. All samples will be immediately frozen and stored at -80°C for further analysis.