Limits...
Does night-time transpiration contribute to anisohydric behaviour in a Vitis vinifera cultivar?

Rogiers SY, Greer DH, Hutton RJ, Landsberg JJ - J. Exp. Bot. (2009)

Bottom Line: Furthermore, Psi(l) fell to significantly lower values than in any of the nine other varieties examined.Night-time values of stomatal conductance (g(n)) and transpiration (E(n)) in Semillon were up to four times higher than in other varieties; plants enclosed in plastic bags overnight to reduce E(n) resulted in better plant-soil equilibration so that predawn Psi(l) in Semillon was the same as in Grenache.The high values of g(day) were associated with high rates of transpiration (E(day)) by Semillon through a day when VPD reached 4.5 kPa.

View Article: PubMed Central - PubMed

Affiliation: National Wine and Grape Industry Centre, NSW Department of Primary Industries and Charles Sturt University, Wagga Wagga, NSW 2678, Australia. suzy.rogiers@dpi.nsw.gov.au

ABSTRACT
The hypothesis that vines of the Semillon wine grape variety show anisohydric behaviour was tested, i.e. that tissue hydration is unstable under fluctuating environmental conditions. Stomatal conductance and transpiration rates from leaves were measured during the day and at night. Leaf water potential (Psi(l)) in Semillon was negatively correlated to vapour pressure deficit (VPD) both predawn and during the day. Furthermore, Psi(l) fell to significantly lower values than in any of the nine other varieties examined. Night-time values of stomatal conductance (g(n)) and transpiration (E(n)) in Semillon were up to four times higher than in other varieties; plants enclosed in plastic bags overnight to reduce E(n) resulted in better plant-soil equilibration so that predawn Psi(l) in Semillon was the same as in Grenache. These data indicate that the hypothesis is supported, and that night-time transpiration contributes significantly to the low Psi(l) values in Semillon during warm, dry nights. The other contributing factor is daytime stomatal conductance (g(day)), which in Semillon leaves was higher than in other varieties, although the decline in g(day) with increasing VPD was greater in Semillon than in Shiraz or Grenache. The high values of g(day) were associated with high rates of transpiration (E(day)) by Semillon through a day when VPD reached 4.5 kPa. When compared to other varieties, Semillon was not unusual in terms of root length density, stomatal density, xylem sap abscisic acid, or leaf electrolyte leakage. Night-time and daytime water loss and insufficient stomatal regulation therefore account for the tendency to anisohydric behaviour shown by Semillon.

Show MeSH

Related in: MedlinePlus

Transpiration (Eday) and stomatal conductance (gday) of Semillon, Shiraz, and Grenache potted vines in response to VPD ranging from 1.0 kPa to 4.0 kPa. Data are representative of three leaves from each variety.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC2736890&req=5

fig7: Transpiration (Eday) and stomatal conductance (gday) of Semillon, Shiraz, and Grenache potted vines in response to VPD ranging from 1.0 kPa to 4.0 kPa. Data are representative of three leaves from each variety.

Mentions: Leaf gas exchange in response to a VPDl range of 1–4 kPa indicated consistently higher rates of Eday and gday for Semillon leaves compared to Shiraz or Grenache leaves (Fig. 7). Transpiration (Eday) of Semillon (R2=0.68, P <0.0001), Shiraz (R2=0.81, P <0.0001), and Grenache (R2=0.19, P <0.05), were all linearly related to VPDl with regression slopes, respectively, of 1.66±0.24, 0.61±0.05, and 0.44±0.19 mmol m−2 s−1 kPa−1. Stomatal conductance (gday) of Semillon (R2=0.39, P <0.001), Shiraz (R2=0.60, P <0.001), and Grenache (R2=0.21, P <0.05) were inversely related to VPD with regression slopes, respectively, of –0.036±0.009, –0.011±0.001, and –0.014±0.006 mol m−2 s−1 kPa−1. Thus Semillon leaves had steeper responses of both stomatal conductance and transpiration to VPDl than the other two varieties. For example, at the lower VPDs, stomatal conductance of Semillon leaves was double that of Shiraz leaves (0.13 compared to 0.25 mol H2O m−2 s−1) and 2.5-fold that of Grenache leaves (0.10 mol H2O m−2 s−1) while at the higher VPD range, gday in Semillon leaves was 2-fold greater than Grenache leaves. Thus, Semillon stomata remained well open at all VPDs in comparison with stomata of the other cultivars.


Does night-time transpiration contribute to anisohydric behaviour in a Vitis vinifera cultivar?

Rogiers SY, Greer DH, Hutton RJ, Landsberg JJ - J. Exp. Bot. (2009)

Transpiration (Eday) and stomatal conductance (gday) of Semillon, Shiraz, and Grenache potted vines in response to VPD ranging from 1.0 kPa to 4.0 kPa. Data are representative of three leaves from each variety.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2736890&req=5

fig7: Transpiration (Eday) and stomatal conductance (gday) of Semillon, Shiraz, and Grenache potted vines in response to VPD ranging from 1.0 kPa to 4.0 kPa. Data are representative of three leaves from each variety.
Mentions: Leaf gas exchange in response to a VPDl range of 1–4 kPa indicated consistently higher rates of Eday and gday for Semillon leaves compared to Shiraz or Grenache leaves (Fig. 7). Transpiration (Eday) of Semillon (R2=0.68, P <0.0001), Shiraz (R2=0.81, P <0.0001), and Grenache (R2=0.19, P <0.05), were all linearly related to VPDl with regression slopes, respectively, of 1.66±0.24, 0.61±0.05, and 0.44±0.19 mmol m−2 s−1 kPa−1. Stomatal conductance (gday) of Semillon (R2=0.39, P <0.001), Shiraz (R2=0.60, P <0.001), and Grenache (R2=0.21, P <0.05) were inversely related to VPD with regression slopes, respectively, of –0.036±0.009, –0.011±0.001, and –0.014±0.006 mol m−2 s−1 kPa−1. Thus Semillon leaves had steeper responses of both stomatal conductance and transpiration to VPDl than the other two varieties. For example, at the lower VPDs, stomatal conductance of Semillon leaves was double that of Shiraz leaves (0.13 compared to 0.25 mol H2O m−2 s−1) and 2.5-fold that of Grenache leaves (0.10 mol H2O m−2 s−1) while at the higher VPD range, gday in Semillon leaves was 2-fold greater than Grenache leaves. Thus, Semillon stomata remained well open at all VPDs in comparison with stomata of the other cultivars.

Bottom Line: Furthermore, Psi(l) fell to significantly lower values than in any of the nine other varieties examined.Night-time values of stomatal conductance (g(n)) and transpiration (E(n)) in Semillon were up to four times higher than in other varieties; plants enclosed in plastic bags overnight to reduce E(n) resulted in better plant-soil equilibration so that predawn Psi(l) in Semillon was the same as in Grenache.The high values of g(day) were associated with high rates of transpiration (E(day)) by Semillon through a day when VPD reached 4.5 kPa.

View Article: PubMed Central - PubMed

Affiliation: National Wine and Grape Industry Centre, NSW Department of Primary Industries and Charles Sturt University, Wagga Wagga, NSW 2678, Australia. suzy.rogiers@dpi.nsw.gov.au

ABSTRACT
The hypothesis that vines of the Semillon wine grape variety show anisohydric behaviour was tested, i.e. that tissue hydration is unstable under fluctuating environmental conditions. Stomatal conductance and transpiration rates from leaves were measured during the day and at night. Leaf water potential (Psi(l)) in Semillon was negatively correlated to vapour pressure deficit (VPD) both predawn and during the day. Furthermore, Psi(l) fell to significantly lower values than in any of the nine other varieties examined. Night-time values of stomatal conductance (g(n)) and transpiration (E(n)) in Semillon were up to four times higher than in other varieties; plants enclosed in plastic bags overnight to reduce E(n) resulted in better plant-soil equilibration so that predawn Psi(l) in Semillon was the same as in Grenache. These data indicate that the hypothesis is supported, and that night-time transpiration contributes significantly to the low Psi(l) values in Semillon during warm, dry nights. The other contributing factor is daytime stomatal conductance (g(day)), which in Semillon leaves was higher than in other varieties, although the decline in g(day) with increasing VPD was greater in Semillon than in Shiraz or Grenache. The high values of g(day) were associated with high rates of transpiration (E(day)) by Semillon through a day when VPD reached 4.5 kPa. When compared to other varieties, Semillon was not unusual in terms of root length density, stomatal density, xylem sap abscisic acid, or leaf electrolyte leakage. Night-time and daytime water loss and insufficient stomatal regulation therefore account for the tendency to anisohydric behaviour shown by Semillon.

Show MeSH
Related in: MedlinePlus