© Triveni Enterprises, Lucknow (India) ISSN : 0254-8704 http : //www.geocities.com/j_environ_biol/
J. Environ. Biol. 29(3), 397-406 (2008)
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Diurnal photosynthesis, water use efficiency and light use efficiency of wheat under Mediterranean field conditions Fatih Evrendilek*1, Jiftah Ben Asher2 and Mehmet Aydin3 1
Department of Environmental Engineering, Faculty of Engineering and Agriculture, Abant Izzet Baysal University, Golkoy Campus, 14280 Bolu, Turkey 2 Department of Dryland Agriculture, Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 684993, Israel 3 Department of Soil Science, Mustafa Kemal University, Antakya-Hatay, 31034, Turkey (Received: July 27, 2006; Revised received: November 02, 2006; Accepted: December 15, 2006)
Abstract: Photosynthesis and transpiration rates of wheat leaves (Triticum aestivum L.) were measured at 30 min intervals under Mediterranean field conditions, using Photosynthesis Monitor system (PM-48M). The dynamics of net photosynthetic rate (PN ), transpiration rate (ET ) , water use efficiency (WUE), light use efficiency (LUE), stomatal conductance (gs ), photosynthetically active radiation (PAR), air temperature (T), relative humidity (RH), and atmospheric CO2 concentration (Catm ) were quantified at five rainfed wheat sites with the same stages of development (midflowering) along south-to-north and east-to-west transects for eight days in April. Diurnal PN (3.6 to 6.6 µmol m-2 s-1), PAR (392 to 564 µmol m-2 sec-1), LUE (0.006 to 0.015) and WUE (0.0001 to 0.011) did not vary significantly across all five wheat sites (p>0.05). PN and ET were strongly coupled and highly correlated with PAR (p