Effects of deficit irrigation on the yield and yield components of drip irrigated cotton in a mediterranean environment

A field study on cotton (Gossypium hirsutum L., cv.) was carried out from 2005 to 2008 in the Çukurova Region, Eastern Mediterranean, Turkey. Treatments were designated as I100 full irrigation; DI70, DI50 and DI00 which received 70, 50, and 0% of the irrigation water amount applied in the I100 treatment. The irrigation water amount to be applied to the plots was calculated using cumulative pan evaporation that occurred during the irrigation intervals. The effect of water deficit or water stress on crop yield and some plant growth parameters such as yield response, water use efficiencies, dry matter yield (DM), leaf area index (LAI) as well as on lint quality components was evaluated. The average seasonal evapotranspiration ranged from 287±15 (DI00) to 584±80mm (I100). Deficit irrigation significantly affected crop yield and all yield components considered in this study. The average seed cotton yield varied from 1369±197 (DI00) to 3397±508kgha-1 (I100). The average water use efficiency (WUEET) ranged from 6.0±1.6 (I100) to 4.8±0.9kgha-1mm-1 (DI00), while average irrigation water use efficiency (WUEI) was between 9.4±3.0 (I100) and 14.4±4.8kgha-1mm-1 (DI50). Deficit irrigation increased the harvest index (HI) values from 0.26±0.054 (I100) to 0.32±0.052kgkg-1 (DI50). Yield response factor (Ky) was determined to be 0.98 based on four-year average. Leaf area index (LAI) and dry matter yields (DM) increased with increasing water use. This study demonstrated that the full irrigated treatment (I100) should be used for semiarid conditions with no water shortage. However, DI70 treatment needs to be considered as a viable alternative for the development of reduced irrigation strategies in semiarid regions where irrigation water supplies are limited. © 2010 Elsevier B.V.European Geosciences Union: INCO-CT-2004-509087The authors would like to gratefully acknowledge the European Union for providing funding through the INCO-CT-2004-509087 STREP DIMAS project. The authors are also thankful to Prof. Elias Fereres, coordinator of the project in the Agronomy Department, University of Cordoba, Spain, for his help and suggestions during the study. Furthermore, we thank Dr. Kenan Diker, Water Quality Control Division, Colorado Department of Public Health and Environment, 80246, Denver, CO, USA and Dr. Ann Diker, Assistant Professor, Metropolitan State College of Denver, Denver, CO, USA, for their help in preparing the manuscript

A comparative field study of the alternate every other furrow surge irrigation and the every furrow surge irrigation techniques

This study was conducted in order to compare the alternate every other furrow surge irrigation (AFO) to the every furrow surge irrigation (EFO), under Mediterranean conditions in Turkey at the Çukurova University experimental farm. The experiment was undertaken in order to determine the appropriate throughput at furrow lengths of 110 m. In general, depending on the water flow (0.87-1.16 L/s) and the duration of the irrigation application (228-272 min), there may be differences on the amount of water under the same flow rates with the use of similar forms of operating furrow application of the AFO, which was determined to be more advantageous than the application of the EFO. The application efficiencies were quite similar by 78% in the EFO and 84% in the AFO, respectively. The reason for these high efficiencies was found to be due to the lacking irrigation application concerning the time of irrigation and the rate of water flow. Significant water savings were achieved by AFO compared to the EFO technique in the field by using the furrows in turns at each irrigation operation. The average soybean yields for both two years were 252 kg/da for the EFO and 259 kg/da for the AFO application. The results of the experiment revealed that the AFO furrow irrigation technique was the appropriate surface irrigation technique for the studied area

Component-Based Method Development: An Experience Report

International audienceA method defines a systematic process for problem solving including the required aids and resources. This paper aims at contributing to the area of method development and in particular to practices and experiences in this field by reporting on a case from conceptual modelling and reflecting on lessons learned in it. The contributions of the paper are (1) an application case from method development in a distributed team, (2) the actual method development process integrating work procedure, cooperation principles and notation, and (3) experiences and lessons learned from developing a method component for context modeling

Music in the exercise domain: A review and synthesis (Part I)

This article is made available through the Brunel Open Access Publishing Fund and can be accessed from the links below - Copyright @ 2012 Taylor & Francis.Since a 1997 review (Karageorghis & Terry) which highlighted the state of knowledge and methodological weaknesses, the number of studies investigating musical reactivity in relation exercise has swelled considerably. In this two-part review paper, the development of conceptual approaches and mechanisms underlying the effects of music are explicated (Part I), followed by a critical review and synthesis of empirical work (spread over Parts I and II). Pre-task music has been shown to optimise arousal, facilitate task-relevant imagery, and improve performance in simple motoric tasks. During repetitive, endurance-type activities, self-selected, motivational, and stimulative music has been shown to enhance affect, reduce ratings of perceived exertion, improve energy efficiency, and lead to increased work output. There is some evidence to suggest that carefully-selected music can promote ergogenic and psychological benefits during high intensity exercise, although it appears to be ineffective in reducing perceptions of exertion beyond the anaerobic threshold. The effects of music appear to be at their most potent when it is used to accompany self-paced exercise or in externally valid conditions. When selected according to its motivational qualities the positive impact of music on both psychological state and performance is magnified. Guidelines are provided for future research and exercise practitioners