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Hazelnut providing the macro-and micronutrients is a constituent of the healthy diet. Hazelnut, one of the most consumed treenut, is produced in the different countries. The geographical origin influences the chemical composition and the biological activity in the several plant foods. The purpose of this study is to evaluate the chemical composition, the antioxidative capacity and total phenolic content of the hazelnut kernels obtained from the different countries, including Azerbaijan, Chile, Italy, and Turkey. The hazelnut kernels were examined for crude oil, ash, moisture, and protein contents. The refractive index, iodine value, and fatty acid composition of the hazelnut oils were identified. In addition, the hazelnut oil, the kernels, and the defatted kernels were tested for their antioxidative activities and total phenolic contents. Protein contents of the hazelnuts from different countries were similar. The largest oil yield was determined in the hazelnut kernels from Chile and Turkey (62.35 ± 0.51 % and 62.29 ± 0.46 %, respectively). While the oil from Turkish hazelnut kernels showed the highest oleic acid content (84.09 ± 0.17 %), Azerbaijan hazelnut oil had the lowest oleic acid content (78.10 ± 0.48). The highest phenolic content was detected in the hazelnut kernels from Azerbaijan. Although the lowest phenolic content was observed in the hazelnut kernels from Turkey, the most potent antioxidative capacity was determined in the Turkish hazelnut kernels, their oil, and their defatted form. It can be concluded that the Turkish hazelnut kernels could contain high amounts of the fat-soluble antioxidants in addition to the water-soluble phenolic antioxidants. The results suggested that the hazelnuts exhibited different chemical composition, antioxidant capacity, and phenolic content depending on their origin. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate long-term seasonal trends and decadal change patterns of monthly mean water vapor pressure (WVP) observation series at 16 meteorological stations scattered point-wisely over the Southeastern Anatolian Project (GAP) area in Turkey, where large-scale soil and water development projects have been put into practice since the 1970s. The record length of WVP observation series of each station varied between 31- and 41-years between 1962 and 2002. The monthly mean WVP observation series of each station was rearranged on seasonal basis. Sequential Mann--Kendall trend test, Sen's slope estimator, and Spearman's rank--order correlation tests were employed for detection of likely trends, and Kruskall--Wallis test was used to detect decadal variations in WVP series of each observation station. A possible area of representation for each meteorological station was determined by using the Thiessen polygons technique in a geographical information systems media. It was found that 15 seasonal WVP series have a positive trend covering 97% of the GAP area in the summer season; although one WVP series has a negative trend direction. However, in the spring season, 33% of the area had a positive trend, and a negative trend did not appear in any stations. WVP records in the winter season showed an increasing trend over 19% of the GAP area, whereas a decreasing trend prevailed in 9% of the area. The study results led us to conclude that the substantial increase of WVP observations in summer season could be attributed to both the shift from rain-fed agriculture to irrigated agriculture being made increasingly spacious year by year and building large water reservoirs in the GAP located in a semi-arid region. The results also indirectly suggested that the historical trends in the WVP parameters might be related to global climate change phenomenon. [ABSTRACT FROM AUTHOR]

Abstract: A study was conducted to determine the effects of different drip irrigation regimes on yield and yield components of cucumber (Cucumbis sativus L.) and to determine a threshold value for crop water stress index (CWSI) based on irrigation programming. Four different irrigation treatments as 50 (T-50), 75 (T-75), 100 (T-100) and 125% (T-125) of irrigation water applied/cumulative pan evaporation (IW/CPE) ratio with 3-day-period were studied. Seasonal crop evapotranspiration (ETc) values were 633, 740, 815 and 903mm in the 1styear and were 679, 777, 875 and 990mm in the 2ndyear for T-50, T-75, T-100 and T-125, respectively. Seasonal irrigation water amounts were 542, 677, 813 and 949mm in 2002 and 576, 725, 875 and 1025mm in 2003, respectively. Maximum marketable fruit yield was from T-100 treatment with 76.65tha−1 in 2002 and 68.13tha−1 in 2003. Fruit yield was reduced significantly, as irrigation rate was decreased. The water use efficiency (WUE) ranged from 7.37 to 9.40kgm−3 and 6.32 to 7.79kgm−3 in 2002 and 2003, respectively, while irrigation water use efficiencies (IWUE) were between 7.02 and 9.93kgm−3 in 2002 and between 6.11 and 8.82kgm−3 in 2003. When the irrigation rate was decreased, crop transpiration rate decreased as well resulting in increased crop canopy temperatures and CWSI values and resulted in reduced yield. The results indicated that a seasonal mean CWSI value of 0.20 would result in decreased yield. Therefore, a CWSI=0.20 could be taken as a threshold value to start irrigation for cucumber grown in open field under semi-arid conditions. Results of this study demonstrate that 1.00IW/CPE water applications by a drip system in a 3-day irrigation frequency would be optimal for growth in semiarid regions. [Copyright &y& Elsevier]