Muscadine grapes have not gained popularity as table grape over bunch grape because of their thick leathery skin

The Department of Agriculture National Institute of Food and Agriculture awarded Florida A & M University $491,739.82 on January 1, 2026, under the 1890 Institution Capacity Building Grants program (CFDA 10.216) to develop non-leathery, crispy muscadine grapes suitable for table-grape markets while retaining pest tolerance and disease resistance traits.

The project integrates genomics, transcriptomics, proteomics, metabolomics, and bioinformatics to identify and characterize genes, transcripts, proteins, and metabolites associated with leathery-skin traits in selected muscadine and bunch grape cultivars. The recipient will validate associations through quantitative reverse transcription polymerase chain reaction (qRT-PCR), phenotyping, and biochemical analysis. The work will evaluate target genes in a heterologous model system (tomato) and apply CRISPR-Cas9 gene editing to modulate expression of genes controlling skin leatheriness, aiming to produce non-leathery muscadine grapes without genetic modification. The project will simultaneously build Florida A & M University capacity in omics technologies.

Performance occurs at Tallahassee, Florida, with the award period running from January 1, 2026, through December 31, 2028. The 1890 Institution Capacity Building Grants program is designed to strengthen research, Extension, and teaching in food and agricultural sciences by building institutional capacities of the 1890 land-grant universities, which are historically Black institutions established under the Second Morrill Act of 1890.

Although the thick leathery skin enhances muscadine berry tolerance to pests, diseases, storage and transportability but diminishes palatability by reducing crispness. Therefore, developing non-leathery crispy muscadine grape with moderately thick skin will be the best compromise to retain all the desirable traits for promoting its acceptability as table grape. Unfortunately, the introgression of non-leathery skin trait into muscadine grape from bunch grape is not feasible through classical breeding due to their genetic incompatibility (40 VS 38 chromosome). Moreover, the skin-associated genes, specifically those linked to cuticle, epidermis or hypodermis formation contributing to leatheriness trait of grape berry have not been identified or characterized in muscadine or bunch grapes. Therefore, we propose to take an integrated approach of genomics, transcriptomics, proteomics, metabolomics and bioinformatics to identify and characterize the gene(s), transcripts, proteins, and metabolites associated with leathery skin trait from selected muscadine and bunch cultivars and determine their association with skin leatheriness through QRT-PCR, phenotyping, and biochemical analyses. The role of the identified gene(s) will be evaluated in a heterologous model system (tomato) and validated by PCR/QRT-PCR and phenotyping. The crispr-CAS9 gene editing system will be applied to modulate the expression of target gene(s) for producing non-leathery crispy muscadine grape. Outcome of this project will yield non-genetically modified muscadine grape with non-leathery skin and concurrently help build capacity and competency of florida a & m university in omics technologies.