Plant growth and water use of container-grown Photinia × fraseri (Dress) were studied under varying irrigation regimes. Treatments were based on management allowed deficit (MAD) irrigation (including 0, 5, 10, 25, 50, 75 and 95% MAD), which links evapotranspiration (ET) and plant available moisture in determining irrigation schedules. Plant growth was maximized under 25% MAD irrigation. Plant performance and water use were significantly reduced as moisture deficit levels in the growing medium exceeded 50% under MAD irrigation of 50%, 75% and 95%. Plant performance also tended to decrease, but plant water use increased with lower MAD treatments (i.e., 0%, 5%, 10%). The research reported provides a model for nursery managers and researchers to use MAD irrigation in determining optimum irrigation regimes to meet plant water needs and maintain maximum plant performance.
Texas Agricultural Experiment Station Journal Article no. TA 30897. We gratefully thank Hines Nurseries, Inc., Houston, TX for donation of plant materials and W.R. Grace, Co., Cambridge, MA for donation of growing media.
2Extension Horticulturist and Associate Professor, respectfully.