Adjustments of water use efficiency by stomatal regulation during drought and recovery in the drought-adapted Vitis hybrid Richter-110 (V. berlandieri x V. rupestris).
The hybrid Richter-110 (Vitis berlandieri x Vitis rupestris) (R-110) has the reputation of being a genotype strongly adapted to drought. A study was performed with plants of R-110 subjected to water withholding followed by re-watering. The goal was to analyze how stomatal conductance (g(s)) is regulated with respect to different physiological variables under water stress and recovery, as well as how water stress affects adjustments of water use efficiency (WUE) at the leaf level. Water stress induced a substantial stomatal closure and an increase in WUE, which persisted many days after re-watering. The g(s) during water stress was mainly related to the content of ABA in the xylem and partly related to plant hydraulic conductivity but not to leaf water potential. By contrast, low g(s) during re-watering did not correlate with ABA contents and was only related to a sustained decreased hydraulic conductivity. In addition to a complex physiological regulation of stomatal closure, g(s) and rate of transpiration (E) were strongly affected by leaf-to-air vapor pressure deficit (VPD) in a way dependent of the treatment. Interestingly, E increased with increasing VPD in control plants, but decreased with increasing VPD in severely stressed plants. All together, the fine stomatal regulation in R-110 resulted in very high WUE at the leaf level. This genotype is revealed to be very interesting for further studies on the physiological mechanisms leading to regulation of stomatal responsiveness and WUE in response to drought.
Grup de Recerca en Biologia de les Plantes en Condicions Mediterrànies, Departament de Biologia, Universitat de les Illes Balears, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Balears, Spain.
Alícia
A
Pou
Jaume
J
Flexas
Maria del Mar
Mdel M
Alsina
Josefina
J
Bota
Cecilia
C
Carambula
Felicidad
F
de Herralde
Jeroni
J
Galmés
Claudio
C
Lovisolo
Miguel
M
Jiménez
Miquel
M
Ribas-Carbó
Denis
D
Rusjan
Francesca
F
Secchi
Magdalena
M
Tomàs
Zsolt
Z
Zsófi
Hipólito
H
Medrano
D000222:Adaptation, Physiological / Q000502:physiology; D055864:Droughts; D006824:Hybridization, Genetic; D018515:Plant Leaves / Q000378:metabolism / Q000502:physiology; D054046:Plant Stomata / Q000378:metabolism / Q000502:physiology*; D018526:Plant Transpiration / Q000502:physiology; D027843:Vitis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D014867:Water / Q000378:metabolism*
D014867:Water