A demand-based irrigation system was developed for Hibiscus rosa-sinensis 'Cashmere Wind' based on the relationship between photosynthesis and substrate moisture level (moisture response curve). An experiment was conducted to evaluate the premise that biomass would decrease only when substrate moisture levels caused a significant reduction in photosynthetic rate. Irrigation set points were based on the moisture response curve and corresponded to 49, 41, 30, and 22m 3m -3 volumetric water content (89-61% container capacity). Gas exchange and leaf water potential were greater for plants in the three wettest irrigation treatments. Plants under these treatments used 1.4, 1.2, and 1.05 times more water during the experiment than plants in the driest treatment. Biomass metrics were generally unaffected by treatments or were greater for one or both intermediate treatments. This research demonstrates that a demand-based irrigation system with a physiological basis (predicated on the relationship between photosynthesis and substrate moisture potential) could be an effective biorational approach for scheduling irrigation and reducing water consumption in container-grown nursery crops.
|Number of pages||6|
|State||Published - May 1 2012|
Bibliographical noteFunding Information:
The authors wish to acknowledge the contributions of Richard S. Gates, Joey Norikane, Doug Archbold, Dewayne Ingram, Sharon Kester, Amy Poston, Leah Dougherty, and Chlodys Johnstone and financial support from the University of Kentucky New Crop Opportunities Center and the University of Kentucky Nursery Landscape mini-grant.
- Nursery crop
- Woody plant
ASJC Scopus subject areas