Thursday, November 16, 2006 - 8:45 AM
316-4

ET and Consumtive Water Use of Saltgrass Bermudagrass and Seashore Pasplaum in a Dry Climate.

Stephen Nolan1, Mohammed Pessarakli1, Paul Brown1, Jim Walworth1, Jeff Gilbert2, and David Kopec3. (1) "Univ. of Arizona, Dept of Plant Sci", "Forbes Bldg, Room 303", "Forbes Bldg, Room 303", Tucson, AZ 85721, United States of America, (2) Tucson, AZ 85721, United States of America, (3) University of Arizona, Room 303, Bldg 36, Tucson, AZ 85721

Using gravimetric lysimeters, the consumptive water use (ET mm/day) was measured  for Sea Isle 1 Seashore paspalum, Tifway 419  bermudagrass and Saltgrass clones A 48, and A 119 in the summer of 2005.  Turfs were maintained at 3.7 cm and soil moisture was not limiting.   The main affect of grasses was significant for fifty out of fifty six ET measurement days (from June 1 to Set 15 2005).   Seashore Paspalum generally had the highest ET rates  for daily ET measurement s, ET  cycle totals, monthly summation totals, and seasonal water use (56 day sum).  Seashore paspalum had the statistically greatest ET rates in June and July, and was equal in August and September for ET with A 119 saltgrass. Bermudagrass always had a statistically lower ET rate (and consumptive water use values) than seashore paspalum.  The combined water use of Saltgrass A 48 and A 19, was statistically less than that of the combined water use of Sea Isle 1seashore paspalum and Tifway bermudagrass ( for the sum of 56 daily ET measurements).  Among the summed total CWU values (for 56 measurement days) , Seashore paspalum used 495 mm of water, Tifway bermudagrass, used 429 mm, A 48 saltgrass used 405 mm, and A 119 saltgrass used 425 mm water. Therefore , Tifway bermudagrass, A 48 and  A 119 saltgrass used 87%, 81%, and 86% of the water respectively , of  that of  Sea Isle 1 paspalum when soil moisture was not limiting.

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