the past decades, lightweight, hand-held, portable, and battery operated infrared thermometers (IRT) became Corn (Zea mays L.) grown under a Mediterranean semiarid climate available. Infrared thermometers can rapidly measure requires supplemental irrigation to maximize the grain yield. Since the cost of irrigation application has been increasing, elimination of canopy temperatures over large areas. The theory of unnecessary irrigation applications would improve economics of corn IRT operation (Fuchs and Tanner, 1966; Fuchs et al., production. There has been much interest in the crop water stress 1967; Hatfield, 1990; Gardner and Shock, 1989); and index (CWSI) as a potential tool for irrigation scheduling and yield (Gardner et al., 1992a) and temperature effects in infraestimation. An experiment was conducted to monitor and quantify red thermometry (Jackson and Idso, 1969) have been water stress, and to develop parameters for irrigation scheduling and discussed. In the 1980s, the use of IRT become more grain yield of summer-grown corn as a function of CWSI under Mediroutine in irrigation scheduling when Idso et al. (1981a) terranean semiarid cropping conditions. Three irrigation treatments developed and demonstrated an empirical method for were based on replenishing the 0.9-m deep root zone to field capacity using the crop water stress index (CWSI). when the soil water level dropped to 25, 50, and 75% of available Idso et al. (1981a) observed a linear relationship bewater holding capacity (AWHC). A dryland treatment was also included. The lower (nonstressed) and upper (stressed) baselines were

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Remotely sensed data is an important tool for precision crop management. Satellite imaging systems and related-hand held instruments are frequently proposed for detection of crop stress caused by water, soil compaction and lack of nutrients, etc. This study was conducted to investigate how Bermuda grass reflectance changes with the onset of water stress. Four different irrigation treatments were examined: 100% (I 1 ), 75% (I 2 ), 50% (I 3 ) and 25% (I 4 ) of the evaporation measured in the Class A Pan. A non-irrigated plot was used as a control treatment (I 5 ). Spectral reflectance data were collected using a hand-held spectroradiometer which measured in the blue, green, red and near-infrared. Soil water content was monitored by a neutron probe. Water-stressed Bermuda grass (treatments I 4 and I 5 ) had lower spectral reflectance in near-infrared and higher reflectance in red wavebands than the other A07029;treatments. The results were statistically tested using one-way analysis of variance and Duncan's multiple range test. Highly significant relationships were found between different irrigation treatments and near infrared wavelengths (P <0.01, R 2 =0.94) and between the irrigation treatments and the normalised difference vegetation index (NDVI) (P < 0.01, R 2 = 0.80). Results indicate that different water stress on Bermuda grass could be determined by using spectral reflectance, especially NDVI and near-infrared reflectance regions. Analysis of experimental data indicated that it is possible to use remotely sensed data to develop maps of water stress conditions of Bermuda grass (Cynodon dactylon).

This study was carried out to determine the effects of deficit irrigation on evapotranspiration and quality of bermudagrass (Cynodon dactylon L.) turfgrass cultivars under Mediterranean conditions. Eight bermudagrass turf cultivars ‘Blackjack’, ‘Mohawk’, ‘Princess’, ‘Riviera’, ‘Sahara’, ‘Sultan’, ‘Swi–1044’ and ‘Swi–1045’ were used. Irrigation experiments were conducted from June to October 2008. Experimental plots were irrigated at 7 days intervals, at three levels of irrigation based on the potential evaporation as measured by a Class A pan (Epan) as follows I1 = 0.50 Epan, I2 = 0.75 Epan and I3 = 1.00 Epan. Volumetric soil water content was measured using soil moisture meter before and after irrigation. It was found that the irrigation levels affect sward color, visual quality and leaf firing. Among the cultivars, ‘Swi–1045’ and ‘Princess’ showed the best color and quality while ‘Mohawk’ and ‘Sultan’ gave the poorest color and quality in all irrigation levels. No statistically significant differences between I1 and I2 irrigation treatments were obtained in terms of color, quality and leaf firing for bermudagrass cultivars. It is concluded that when the amount of water is limited in arid and semiarid regions such as the Mediterranean, the bermudagrass can be irrigated at a level of 50% of pan evaporation to get an acceptable visual quality with improved water conservation.