The tolerance of grapevine rootstocks to water deficit is related to root morphology and xylem anatomy traits
Climate change is altering water balances, thereby compromising water availability for crops. In grapevine, the strategic selection of genotypes more tolerant to soil water deficit can improve the resilience of the vineyard under this scenario. Previous studies demonstrated that root anatomical and morphological traits determine vine performance under water deficit conditions. Therefore, 13 ungrafted rootstock genotypes, 6 commercial (420 A, 41 B, Evex 13-5, Fercal, 140 Ru y 110 R), and 7 from new breeding programs (RG2, RG3, RG4, RG7, RG8, RG9 and RM2) were evaluated in pots during 2021 and 2022. Well-watered plants were subjected to progressive water deficit and subsequent recovery. Plant water status and hydraulic conductance was determined under different conditions of water availability and, at the end of the experiment, the anatomy of the vascular system and root morphology were characterized by using optical microscopy and WinRHIZO software respectively. The results showed a great anatomical diversity of xylem among the genotypes studied. The greater proportion of fine roots and the smaller diameter of the xylem vessels seem to be key traits in the tolerance to severe stress and the recovery capacity. The genotypes 420 A and RM2 (common parent V. Berlandieri), showed greater tolerance to severe stress and recovery capacity. On the other hand, the new RG series did not show clear advantages of adaptation to stress compared to commercial rootstocks. These findings improve the understanding of the role of root anatomy and morphology in vine responses to water deficit providing a basis for future breeding programs.
Issue: ICGWS 2023
1Agro-environmental and Water Economy Research Institute-University of Balearic Islands (INAGEA-UIB)
2Research group of plant biology under Mediterranean Conditions – University of Balearic Islands (PlantMed-UIB)
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hydraulic conductance, plant water status, drought, climate change, xylem vessels, root diameter