Author
HUGALDE, INES - National Institute Of Agricultural Technology(INTA) | |
RIAZ, SUMMAIRA - University Of California | |
AGUERO, CECILIA - University Of California | |
BARRIOS-MASIAS, FELIPE - University Of Nevada | |
NGUYEN, ANDY - University Of California | |
VILA, HERNAN - National Institute Of Agricultural Technology(INTA) | |
McElrone, Andrew | |
GOMEZ TALQUENCA, SEBASTIAN - National Institute Of Agricultural Technology(INTA) | |
WALKER, M. ANDREW - University Of California |
Submitted to: Acta Horticulturae
Publication Type: Proceedings Publication Acceptance Date: 11/1/2017 Publication Date: 2/1/2017 Citation: Hugalde, I., Riaz, S., Aguero, C.B., Barrios-Masias, F., Nguyen, A.V., Vila, H., Mcelrone, A.J., Gomez Talquenca, S., Walker, M. 2017. Physiological and genetic control of vigour in a 'Ramsey' x 'Riparia Gloire de Montpellier' population. Acta Horticulturae. 1188:205-212. https://doi.org/10.17660/ActaHortic.2017.1188.27. DOI: https://doi.org/10.17660/ActaHortic.2017.1188.27 Interpretive Summary: Vigour, a highly quantitative character, is particularly difficult to address. A large number of variables need to be studied in order to achieve a fine comprehension of the phenomena involved. In our study, we analyzed vigour from a wide physiological view and a genetic mapping approach. For quantitative characters, where positive feedbacks (typically exponential) can cause large effects, low but statistically significant explanatory levels, like the QTLs found, as well as the physiologic results, may have impressive effects. The variables that were mapped, and for whom significant QTLs were found, had been previously identified as highly significant in the ACP analyses for 2014 and 2015, indicating the importance of these traits in the determination of vigour. Furthermore, the genome-wide 210 QTLs we identified represent variables that are tightly correlated to leaf area and canopy biomass, the major vigour identification traits. Technical Abstract: Vigour control in grapevine can be achieved by grafting with particular rootstocks, and may become especially important under climate change. This research studied the F1 progeny from the cross of Ramsey X Riparia Gloire de Montpellier rootstocks, known to confer high and low vigour, respectively. We hypothesized that vigour correlates with growth rate, leaf area, biomass partitioning, plant hydraulics and gas exchange; and that these variables could be associated with genetic 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 area and 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 initial weight at full pot capacity, and plant and root hydraulic conductances, stomatal conductance and water potential were measured. The progeny showed transgressive segregation and significant differences in vigour. A PCA analysis showed a strong role for shoot growth rate, specific leaf area, plant hydraulics and partitioning indices for vigour determination. Under water stress, larger plants showed less specific hydraulic and stomatal conductances, indicating higher sensibility upon drought. Significant QTLs for leaf area, specific leaf area and partitioning indices were found on chromosomes 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 partitioning indices in 2014. Mapping data from 2015 is being analyzed. |