Location: Plant Genetic Resources Unit (PGRU)Title: Phenological diversity in wild and hybrid grapes (Vitis) from the USDA-ARS cold-hardy grape collection
Submitted to: Planta
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/7/2021
Publication Date: N/A
Interpretive Summary: The seasonal timing of plant growth, or phenology, is an important factor in determining where plant varieties can be grown. We explored this diversity in the United States Department of Agriculture cold-hardy grape collection, in Geneva, NY. We measured budbreak (when vines resume growth during spring), bloom, and veraison (the onset of fruit color during prior to maturation), in 1,583 unique vines representing 20 species of grapes, including the cultivated wine and table grapes as well as wild grapes. We observed significant variation in these traits and classified the vines as early, intermediate, or late for each stage. This knowledge is important when selecting suitable grape varieties for a growing region and for developing new varieties through plant breeding.
Technical Abstract: Wild grape relatives and hybrids have been useful in breeding for tolerance to biotic and abiotic stress, however, few studies have emphasized wild and hybrid grapevines for phenological diversity. Utilization of phenological diversity in grapevine breeding could facilitate expansion of grape production into more varied climate regions. Budbreak, bloom, and veraison observations for 1,583 accessions from 20 taxa from the United States Department of Agriculture Vitis collection in Geneva, New York, USA. Genotypic and species variation were estimated. Vitis vinifera ancestry was estimated in Vitis hybrids using principal components analysis. Observations ranged 26.6 to 162.1 (79 to 141 JD) with an average of 82.6 GDD (118 JD) for budbreak, 206.8 to 1,055.2 (141 to 222 JD) with an average of 371.9 GDD (163 JD) for bloom, and 849.9 to 1,627.0 (202 to 290 JD) with an average of 1,207.9 GDD (235 JD) for veraison. Seasonal correlations were high for bloom and veraison (0.85 to 0.95) and moderate for budbreak (0.61 to 0.65). Moderate heritability was estimated for veraison (0.62) and bloom (0.49), and weak heritability for budbreak (0.2). The species effect was greatest in bloom and explained 42% of the variation, with increasing bloom GDD associated with increasing contribution of V. vinifera in Vitis hybrids.