Search Results
The primary objective of this research was to determine the evapotranspiration (ET) rates of 10 well-watered St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] genotypes under field conditions and in a controlled-environment chamber with a high evaporative potential. A secondary objective was to correlate ET rate to leaf extension rate, shoot density, and abaxial and adaxial leaf blade stomatal densities. Overall ET rates among genotypes were not significantly different in the field study, but they were significantly different under the higher evaporative potential of the chamber study. ET rates under field conditions were not correlated to ET rates under chamber conditions. ET rates were not correlated to leaf extension rates in the field or chamber. ET rates in the chamber were correlated neither with shoot nor with stomatal densities. Overall ET rates in the field study were not correlated to stomatal densities, but were correlated to shoot density (r = 0.77).
We compared evapotranspiration (ET) rates for 11 Zoysia genotypes, encompassing two species and their hybrid, maintained at nonlimiting soil moisture under field conditions and in an environmental chamber of high evaporative potential. ET rate relationships to leaf area [leaf extension rate (LER)], canopy resistance [shoot density (SHD)], and internal resistance [abaxial (AB) and adaxial (AD) leaf blade stomatal densities] characteristics were determined. Three-year ET rate means were not significantly different among genotypes in the field study, but ET rates among genotypes differed significantly under the higher evaporative potential of an environmental-chamber study. ET rate was not significantly correlated with LER for either the data from the field or the chamber. ET rates of both types of tests also were not significantly correlated with SHD or AB or AD leaf blade stomatal density. Data from field and environmental-chamber research suggest that differences of individual morphological traits among the 11 zoysiagrasses do not influence the ET rate when measured from minilysimeters maintained at nonlimiting soil moisture.