Relationship Between Turfgrass Quality Performance and Evapotranspiration Rate in Cultivars of Kentucky Bluegrass

Breeding turfgrass that combine superior turfgrass performance with a more conservative water use pattern is important in maintaining optimum growth potential and functional quality turf with less water. Morphological characteristics associated with increase canopy resistance to evapotranspiration (ET) and low leaf area have been found to be correlated with reduced ET in well irrigated turfgrass. Canopy resistance and leaf area components are also important turf forming properties. The objective of this study was to determine if superior turfgrass quality in 59 Kentucky blue-grass (Poa pratensis L.) selections maintained under field conditions and optimum cultural intensity was associated with reduced ET measured under well watered, controlled environment conditions. Negative correlations were observed between turf quality rating (rating, 1 to 9,9 = highest) and ET rate (mm d−1, measured at 25°C). Significant correlations (P£ 0.05) were detected between ET rate and quality data from 5 of the 7 National Turfgrass Evaluation Program (NTEP) locations evaluated in the study. Correlations ranged from −0.04 (at East Lansing, MI) to −0.51 (P< 0.001, at Adelphia, NJ). The general pattern between improved turfgrass quality and reduce ET rate in this study indicate that KBG cultivars currently available combine both superior turfgrass performance with conservative water use. However, it is unlikely that this result was achieved from breeding for low water use directly.