Water Productivity of Modern Variety of Paddy Production: Rice-prawn and Year-round Paddy Farming Systems in Bangladesh

Abstract

Rice-prawn gher farming system is an indigenous technology combined form of aquaculture and agriculture solely developed by local farmers since 1980s in the southwestern Bangladesh. This paper aims to estimate the water productivity of modern variety (MV) of paddy production under rice-prawn gher (RPG) and year-round modern variety (YRMV) of paddy farming system. The findings of the study indicate that water productivity of MV paddy production was significantly higher (more than two times) in RPG farming than YRMV paddy farming system. Water use efficiency of irrigation system to MV paddy production was also higher in RPG farming than YRMV paddy farming. Water wastage such as water outflow and runoff were minimum in RPG farming because each gher plot has own canals that retain sufficient water for irrigation, and runoff and outflow water goes into same canals and recycle the water as irrigation again and again during crop growth period. On the other hand, a significant amount of water is used as unproductive purposes such as water outflow and runoff during irrigation to paddy field for long distance paddy field from the source of irrigation in YRMV paddy farming. Per ha irrigation cost of MV paddy production was also lower in RPG farming than YRMV paddy farming system in Bangladesh.