Abstract
Canopy temperature (Tc) provides an easy-to-acquire indication of crop water deficit that has been used in irrigation scheduling systems, but interpretation of this measurement has proven difficult. We compared the timing of irrigation application of the Stress Time (ST) method of irrigation scheduling with the Stress Degree Hours (SDH) method on deficit irrigated cotton (Gossypium hirsutum L.) where each irrigation event delivered 5 mm of water through subsurface drip tape. A well-watered (WW) control and a dry land (DL) treatment were also part of the experimental design. We used data collected from the WW and DL treatments to develop upper and lower baselines for the Crop Water Stress Index (CWSI) appropriate for cotton grown at our location. The ST method detected drought stress earlier in the growing season when both the SDH and CWSI indicated very little drought stress. The SDH method resulted in the application of irrigations relatively later in the growing season when the CWSI also detected higher levels of drought stress. These results suggest that the adding certain micrometeorological variables to simple Tc methods of deficit irrigation scheduling may improve the ability to detect and quantify the degree of crop drought stress.
Original language | English |
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Pages (from-to) | 40-49 |
Number of pages | 10 |
Journal | Plant Biosystems |
Volume | 147 |
Issue number | 1 |
DOIs | |
State | Published - 10 Jun 2013 |
Keywords
- Canopy temperature
- Cotton
- Irrigation
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Plant Science