Abstract: Due to arid and semi-arid area of Iran, applying optimized irrigation water management solutions to reduce consumption and efficient use of water in plants is essential. In this regard, this research is done in 94-93 crop year in a template design of randomized complete blocks with five treatments of 120% of complete irrigation (T1), 100% (Complete irrigation) (T2), 80% (T3), 60% (T4), 40% of complete irrigation (T5) with four replications at the agricultural research farm of Lorestan University to study the effects of different irrigation levels on yield, yield components, water use efficiency and reaction factor of cowpea product. The results of the study showed that different levels of irrigation water by reducing water consumption, traits such as weight of 100 grains, seeds per pod, seed size, number of pods per plant, pod length, plant height, biological yield and harvest index by reduction and efficiency of water use showed a significant increase. The most efficient water use based on the seed was observed in treatment T80 (0.54). Yield response factor to moisture stress in treatments of 100 and 80% at doses of 0.274 and 0.25 had low sensitivity and in treatments of 60 and 40 the water requirement values of 0.747 and 0.911 had average sensitivity. In this study, the treatment of 80% (T3) with grain yield of 2458 kg/ha by reducing 3.7% in comparison to complete irrigation and saving 20% of water was determined as the best treatment for the cultivation of cowpea in Khorramabad.
Abbas Maleki, Negar Esnaashar and Afsaneh Alinejadian Bidabadi, 2017. Impact of Deficit Irrigation on Yield Components, Water use Efficiency and Yield Response Factor of Cowpea in Khorramabad Iran. Journal of Engineering and Applied Sciences, 12: 2471-2479.