ISHS


Acta
Horticulturae
Home


Login
Logout
Status


Help

ISHS Home

ISHS Contact

Consultation
statistics
index


Search
 
ISHS Acta Horticulturae 171: I International Symposium on Water Relations in Fruit Crops

THE EFFECT OF WATER STRESS AND VAPOR PRESSURE GRADIENT ON STOMATAL CONDUCTANCE, WATER USE EFFICIENCY, AND PHOTOSYNTHESIS OF FRUIT CROPS

Authors:   J.A. Flore, J.W. Moon, A.N. Lakso
DOI:   10.17660/ActaHortic.1985.171.18
Abstract:
The effect of mild water stress on leaf stomatal conductance (gs), photosynthesis (Pn), and water use efficiency (WUE) was determined with an open gas exchange system or with a portable diffusion porometer for apple (Malus domestica Borkh. 'Empire'), and sour cherry (Prunus cerasus L. 'Montmorency'), and highbush (Vaccinium corymbosum L. 'Jersey') and a wild, more drought stress species, Vaccinium darowii, blueberry. Under optimum nonstress conditions, maximum gs values were greatest for cherry, followed by apple, then blueberry. Soil moisture stress decreased gs and Pn in apple and cherry. Stomata on nonstressed plants were more responsive to vapor pressure deficit and seemed less responsive to CO2 gradient than stressed plants. Stomatal aperture decreased in response to increased external CO2 concentration, the degree of response varied with stress. Water use efficiency increased under mild stress conditions. Recovery occurred in 2–3 days after rewatering. Stress conditions could be induced with VFD of 1.5–2.0 kPa when soil moisture conditions were held near field capacity. When grown under optimum soil moisture conditions in a shadehouse (low VPD), plants were more responsive to CO2 gradients than field-grown material. Within the genus Vaccinium, genetic differences existed for the relationship between VPD and stomatal conductance or water use efficiency.

Download Adobe Acrobat Reader (free software to read PDF files)

171_17     171     171_19

URL www.actahort.org      Hosted by KU Leuven      © ISHS