ISHS Acta Horticulturae 171: I International Symposium on Water Relations in Fruit Crops
CHANGE IN TRANSPIRATION RATE OF MATURE CITRUS TREES IN RESPONSE TO A REDUCTION OF WETTED SOIL VOLUME |
| Authors: | Y. Cohen, S. Moreshet, M. Fuchs |
| Abstract:
The effect of different wetted soil volumes on water uptake by "Shamouti" orange (Citrus Sinensis L. Osbeck) trees were examined during two summers in the coastal plain of Israel. Two treatments were applied: one in which 100% of the soil surface was irrigated to a depth of 0.9 m by sprinklers, and the other in which 40% of the soil surface to the same depth was irrigated by sprayers. Irrigations of the two treatments were given whenever the average soil water deficit in the wetted part dropped to a fixed predetermined level. Moisture depletion was measured by the neutron scattering method and transpiration by the heat pulse method. Water application throughout the irrigation period in the partially irrigated plot was 34% less than in the fully irrigated plot. Water uptake by the partially irrigated trees was 15% to 20% lower than the fully irrigated trees. A gradual decrease in sap flow with time after irrigation was measured in both treatments but sap flow in the partially irrigated trees decreased more rapidly than in the fully irrigated trees. The results suggest an increase of water uptake by the root system in the 40% irrigated soil volume, but not to a sufficient level to completely compensate for the reduction in water uptake of the 60% dry volume. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
