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The study aiming to determine the effect of different irrigation regimes and water stress imposed at different growth stages on water use and leaf yield of flue-cured tobacco plant (Nicotiana tabacum L.), was carried out during the period of 2000-03. The field trials were conducted on a silty loam Entisol soil, poor in organic matter and rich in potassium on the fields of the Atatürk Soil and Water Resources Research Institute in Kırklareli. A randomised complete block design with three replications was applied and K-326 Virginia tobacco cultivar was used in the experiment. Three known stages of the plant, vegetative (V), yield formation (F) and ripening (R), were considered and a total of 14 (including rain-fed) irrigation treatments were applied. All the experimental treatments were irrigated on the same day in each growth stage with the amount of water required to fill the 0-90 cm soil depth to field capacity, and three levels of water amount reductions (0, 40 and 60%) were applied at each development stage. A single irrigation was applied during the second part of the vegetative stage, while subsequent water applications were at the 50 and 70% depletion level during the yield formation and ripening stages, respectively. Results of the 3-year study show that either total irrigation water amounts and number of applications, or leaf yields are closely related to precipitation rate and distribution during the growing year. While the seasonal irrigation amounts applied in the adequate irrigation treatment (VFR) were greater (945 and 815 mm respectively in the drier experimental years of 2000 and 2001), they were much lower (587 mm) during the rainy year of 2003. The highest leaf yields in the range of 5170-6050 kg ha À1 were obtained from the fully irrigated programme (VFR), from treatments with 40% reduction in irrigation water amount at any stage (V 1 FR; VF 1 R, VFR 1 ) and irrigation programme (FR) including omitted irrigation at vegetative stage and fully irrigated during the next two stages. It was also determined that close linear relationships exist between seasonal evapotranspiration rate and leaf yield, and seasonal evapotranspiration deficit and relative yield reduction, during each of the experimental years. Copyright

The study aimed to determine the most appropriate irrigation scheduling for mini-type cucumber plants grown as a spring-summer cycle crop. The research was conducted in a greenhouse structure in the fields of the Research Institute in Kirklareli. Marathon cucumber plants were used as the plant material in the trials. The split plot design experimental layout in 3 replications was used in the research. Four different plant-pan coefficients (0.75, 1.00, 1.25 and 1.50) and two irrigation intervals (2 and 4 days) were applied as subplots and main plots of the study, respectively. As a result of the 3-year investigation, it was determined that yields, number of cucumber fruits, and fresh cucumber fruit weight, length and diameter increased with the increase in the irrigation water amount. The highest average total soluble solids (Brix) value of 5.0 was recorded under conditions of most severe stress imposed on the plots with lowest water application rates of Kcp 0.75. While the lowest values of 4.0-4.1 were obtained for plants growing under more favorable moisture conditions in plots with application of Kcp 1.25 and 1.50. Statistically significant positive linear relationships were obtained for irrigation water amount on one hand, and fruit number, fruit mean weight, fruit length and diameter on the other, while the relationship between water applied and TSS (Brix) was negative.

This study includes some deep underground well waters opened to supply the irrigation water in Tekirdağ province. The sampling was done from 22 wells in the irrigation season period. The parameters such as pH, EC, TDS, Na, Ca, Mg, K, Cl, HCO3, B, NO3-N, Sodium Absorption Ratio and Residual Sodium Carbonate parameters, which were significant in terms of irrigation water classification, were examined in the samplings. According to the results, it was determined that thirteen well waters were in medium salty and eight well waters were in high salty water classes. Besides, Na and HCO3 harms were determined in five and three well waters, respectively. In seven well waters, it was concluded that RCE values were over 2,5 me L-1 and these water were not suitable in the usage of irrigation. As a result of the evaluations in terms of the specific ions, it was determined that CL, B and NO3-N concentrations which were found in three, two and one wells respectively, could create damages in some crops. As a result of the evaluations in terms of salinity and SAR parameters, it was concluded that the usage of T5, T6, T8, T10, T13 and T14 well waters was undesirable and the usage of T9, T11, T12, T16, T17 and T21 well waters can be suggested by the provision of some special conditions (appropriate drainage conditions, appropriate plant selection, coarse textured soils).