Shared genetic control of seasonal bud freezing tolerance and winter endurance in an F₂ grapevine population

Abstract

Freezing tolerance is an important trait affecting grapevine winter survival in the Northern United States. This study investigated seasonal grapevine bud freezing tolerance and overall vine winter tolerance in grapevine using an F2 population derived by selfing a single F1 developed from a cross of V. riparia ‘Manitoba 37’ × ‘Seyval blanc’ (VRS-F2). F2 genotypes (113) were established in a vineyard at the N. E. Hansen Research Station, Brookings, SD, USA. Low temperature exotherm analyses (LTE) of 3 replicate buds was measured in November, December, January, February, and March of 2017/18 and 2020/2021 to identify immediate freezing tolerance. Asecond study evaluated overall winter endurance by scoring vine vigor at budbreak eight and nine years after planting. ArhAmpSeq-GBS genetic map was used for QTL identification. The monthly LTE analyses identified three stable QTL, in November and December, on chromosomes 10, 13, and 14, which explained 16 to 27% of the variation. Analysis of the genes underlying the narrowest colocation of each QTL’s 95% Bayesian interval found genes in the early-responsive to dehydration, circadian rhythm, floral development and MADS box transcription factor gene pathways. Whole vine winter endurance measured by vine vigor at budbreak identified a stable QTL on chromosome 4. Analysis of genes underlying the overall winter tolerance loci indicated calcium signaling, flower development, circadian rhythm, and WRKY transcription factor gene pathways. Awhole vine winter endurance QTL on chromosome 14 colocated with LTE QTL in December and November suggesting shared genetic control of the monthly freezing tolerance and overall winter tolerance in the VRS-F2 population.

Acknowledgements

USDANational Institute of Food and Agriculture 2017- 51181-26829 and 2022-51181-38240.