Physiological and genetic control of vigour in a Ramsey × Riparia Gloire de Montpellier population

GÓMEZ TALQUENCA, S.; NGUYEN, A.N.; AGÜERO, C.B.; WALKER, M.A.; MCELRONE, A.; BARRIOS-MASIAS, F.; RIAZ, S.; ARANCIBIA, C.; VILA, H.; ROMERO, N.; HUGALDE, I.

ACTA HORTICULTURAE

International Society for Horticultural Science

Año: 2017

0567-7572

Vigour control in grapevine can be achieved by grafting with particularrootstocks, and may become especially important under climate change. Thisresearch studied the F1 progeny from the cross of ?Ramsey? × ?Riparia Gloire deMontpellier? rootstocks, known to confer high and low vigour, respectively. Wehypothesized that vigour correlates with growth rate, leaf area, biomass partitioning,plant hydraulics and gas exchange; and that these variables could be associated withgenetic markers. We evaluated 138 seedlings from this cross, three replicates each,for 60 days in a greenhouse at UC Davis, California, during summer 2014 and 2015.Each plant was pruned to a single shoot and watered daily. Shoot growth rate, leaf areaand dry biomass were measured for the complete population, both years. In 2014,after day 45, 40 genotypes were subjected to a 50% water deficit, based from initialweight at full pot capacity, and plant and root hydraulic conductance?s, stomatalconductance and water potential were measured. The progeny showed transgressivesegregation and significant differences in vigour. A PCA analysis showed a strong rolefor shoot growth rate, specific leaf area, plant hydraulics and partitioning indices forvigour determination. Under water stress, larger plants showed less specific hydraulicand stomatal conductance?s, indicating higher sensibility upon drought. SignificantQTLs for leaf area, specific leaf area and partitioning indices were found onchromosomes 1, 4, 16, and 5; accounting for 20% of explained variability for leaf area,and from 10 to 14% of explained variability for specific leaf area and partitioningindices in 2014. Mapping data from 2015 is being analysed.