IOSR Journal of Agriculture and Veterinary Science (IOSR-JAVS) e-ISSN: 2319-2380, p-ISSN: 2319-2372. Volume 5, Issue 6 (Nov. - Dec. 2013), PP 82-85 www.iosrjournals.org www.iosrjournals.org 82 | Page Performance of Raised Bed Irrigation in Comparison to AWD and Flood Irrigation for Boro Rice S. M. I. Hossain Department of Agricultural Engineering, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh Abstract: An experiment was conducted in Bangabandhu Sheikh Mujibur Rahman Agricultural University experimental farm to evaluate the performance of raised bed irrigation (RBI) system in comparison to alternate wetting and drying (AWD) and flood irrigation (FI) methods for Boro rice (BR 45) during 2012-2013. Four treatments: irrigation in raised bed two rows (T 1 ), in raised bed three rows (T 2 ), alternate wetting and drying (T 3 ) and flood irrigation (T 4 ) were considered for performance evaluation. The highest grain yield of 5.09 t/ha was produced in treatment T 3 (AWD) followed by treatment T 4 (FI) (4.77 t/ha), T 1 (RBI two rows) (4.69 t/ha) and T 2 (RBI three rows) (3.91 t/ha). The highest water productivity was obtained in treatment T 1 (66.41 kg/ha- cm) followed by treatment T 2 (58.33 kg/ha-cm) and T 3 (48.77 kg/ha-cm). The least amount of water required to produce one kilogram (kg) of rice grain was in treatment T 1 (1556 l/kg) while the highest was in treatment T 4 (2341 l/kg). Treatment T 1 (RBI two rows) and T 2 (RBI three rows) required 34% and 22% less water than the flood irrigation (T 4 ). Therefore, raised bed irrigation can be adopted for Boro rice in water scarce areas. Keywords: AWD, Boro rice, flood irrigation, Raised bed irrigation, water productivity I. Introduction Water is one of the major inputs for crop production. In the dry season, crops are grown through irrigation. Therefore, irrigation plays an important role in crop production that in turn ensures the food security. Water is becoming increasingly scarce worldwide [1]. Irrigation water is also becoming scarce in Bangladesh. With the raising of river and canal beds due to increase of siltation the surface water is being diminished gradually. In addition, surface water (river and canal water) is getting polluted by indiscriminate discharge of industrial effluents. For this reason, groundwater is becoming the major source of irrigation water for crop cultivation which is also depleting rapidly and becoming polluted by heavy metals like arsenic [2,3]. So it is high time to think about the efficient use of irrigation water. The raised bed irrigation for Boro rice can be an effective and proper practice for efficient use of irrigation water for Boro rice production in Bangladesh. Boro rice is conventionally produced by flood irrigation method where water is applied in the plane rice field at a depth of 4 to 5 cm. In this method it requires about 3000 to 5000 liters of water to produce one kilogram of rice [4]. In flood irrigation method exposed water surface allows the highest water loss through evaporation. But, in alternate wetting and drying (AWD) method, it has been reported to save more than 27% of irrigation water and provide higher yield than flood irrigation [5]. It is also reported that the AWD technology can reduce 5 numbers of irrigation compared to conventional flood irrigation and save irrigation water up to 25% [4]. Rice transplanted on furrow irrigated rice bed is comparable with traditional rice culture that can save as much as 25-50% irrigation water [6]. An increased grain yield of 17% was produced in bed planting with 70 cm bed width over conventional method when planted rice in rice-wheat cropping system [7]. Irrigation water in the rice field is used mainly in three ways: water uptakes by the plant through roots which is transpired by the leaves to the atmosphere, water evaporates from the soil surface to the atmosphere and water percolates to the groundwater provided runoff and seepage are properly controlled. Rate of percolation of water is fully controlled by the soil type and that is why there is limited human control over percolation. Water uptakes by the roots is the requirement of the plant and any controlled over the transpiration will hamper plant growth and reduce yield. So, it is essential to provide adequate water for optimum transpiration of plants. In raised bed irrigation there is a limited water surface area for evaporation, which can reduce evaporation loss of water from the irrigation field [8]. Therefore raised bed irrigation can reduce the irrigation water and consequently reduce the cost of irrigation. Hence to increase the water use efficiency and water productivity, it can be effective technology for rice [9]. In raised bed planting of rice, water from furrows flows horizontally to the root zone which reduces the percolation of water from the root and simultaneously decreases the loss of fertilizer with percolation water. This will increase the effective use of fertilizer. It will reduce the water loss through percolation as the percolation will mainly take place from the furrows. So, raised bed will reduce loss of water through percolation and evaporation, and fertilizer loss simultaneously. Thus permanent raised bed system can improve water and