Agricultural Water Management 158 (2015) 225–234 Contents lists available at ScienceDirect Agricultural Water Management jou rn al hom ep age: www.elsevier.com/locate/agwat Water use and yield of sugar beet (Beta vulgaris L.) under drip irrigation at different water regimes Sultan Kiymaz a,∗ , Ahmet Ertek b a Ahi Evran University, Agriculture Faculty-Department of Biosystems Engineering, Kirsehir, Turkey b Suleyman Demirel University, Agriculture Faculty-Department of Irrigation and Drainage, Isparta, Turkey a r t i c l e i n f o Article history: Received 3 September 2014 Received in revised form 30 April 2015 Accepted 5 May 2015 Keywords: Deficit irrigation Sugar beet Water use efficiency Drip irrigation a b s t r a c t This study examines the effects of different irrigation regimes on water use and root yield of sugar beet, irrigated with a drip system under field conditions in the 2012–2013 seasons at Cukurcayir in the Kırsehir Centrum of the Central Anatolian region of Turkey. Experiments were carried out in split plots in randomized blocks with three replications. The application of irrigation water was based on cumulative class A pan evaporation within irrigation intervals. Study treatments consisted of one irrigation interval (7 days); the two sugar beet varieties (C 1 : Esperanza and C 2 : Calixta) and three different irrigation levels (I 1 , I 2 , and I 3 ) adjusted according to the class A pan evaporation (E pan ) using three different plant-pan coefficients (K cp1 : 0.5; K cp2 : 0.75; and K cp3 : 1.00). The lowest and the highest values of irrigation water and plant water consumption (Et) were observed in the I 1 and I 3 treatments in both years, respectively. In 2012, the lowest and the highest root yields were observed in the I 3 C 1 (85.38 t ha -1 ) and I 2 C 2 (75.10 t ha -1 ) treatments. In the second experimental year, the lowest and the highest root yields were achieved with the I 3 C 1 (66.13 t ha -1 ) and I 1 C 2 (47.57 t ha -1 ) treatments, respectively. The impact on the examined parameters of irrigation programs in the C 2 treatment had not significant. On the other hand, in the C 1 treatment of irrigation programs had a significant effect on sugar rate, sugar yield, and other parameters. If the economic yield and quality are desired, the I 1 C 1 treatment can be suggested for sugar beet production under the similar soil and climatic conditions. © 2015 Elsevier B.V. All rights reserved. 1. Introduction Today, about 144 million tons of sugar is produced each year in as many as 127 countries around the world (Thelen, 2004). Worldwide, 80% of the world’s sugar supply comes from sugar- cane, cultivated in tropical climates in developing countries, while the remaining 20% comes from sugar beet that is mainly cultivated in industrialized countries. The largest producing countries are Brazil (25%), India (10%), China (10%) and the 27 European countries (9%), followed far behind by the United States, the Russian Federa- tion, Turkey, Ukraine and Food and Agriculture Organization of the United Nations (FAO, 2009). Sugar beet (Beta vulgaris L.), grown mostly under irrigated condi- tions, is a major commercial field crop in Turkey, and Turkey’s share in world production of beet sugar in 2010/11 was 2.27 million tons, accounting for 8% of the world total. Sugar beet takes an important ∗ Corresponding author. Tel.: +90 386 2804819. E-mail address: skiymaz@ahievran.edu.tr (S. Kiymaz). place among the field crops grown in the Kırsehir Province, given its economic importance as the raw material for the production of sugar. In the Kırsehir Province, the average sugar beet production was 58.2 t ha -1 in 2012 on 49,113 ha of sugar beet growing area (TSFGD, 2013). A common irrigation method in sugar beet production in this region is sprinkler irrigation, and crop yield may increase if proper irrigation methods are followed. Drip irrigation has been shown to reduce irrigation water requirements for a variety of crops under certain circumstances when compared to sprinkler or furrow sys- tems (Kruse et al., 1990), among which can be counted sugar beet (Tognetti et al., 2002). The cost of drip irrigation systems has been declining with the advent of new concepts and materials, and if sugar beet can be proved to be well suited to drip irrigation, farmers with established drip systems may consider including sugar beet in their crop rotations. The appropriate management of irrigation is of vital importance for the preservation of water resources, quantitatively and qualita- tively, and to maximize food production with the available water resources. Irrigation scheduling is one of the most important tools http://dx.doi.org/10.1016/j.agwat.2015.05.005 0378-3774/© 2015 Elsevier B.V. All rights reserved.