Effect of Wastewater Irrigation on Yield, Water Productivity and Economics of Sunflower and Toria Crop

Abstract

Water scarcity is one of the most important issue affecting the global economy and human livelihoods. Climate change, rapid population growth, freshwater pollution and depletion are among the factors exacerbating the situation. Although not yet fully exploited, wastewater reclamation and reuse are considered potential mechanisms to mitigate the challenge. To evaluate the impact of wastewater on yield, economics, soil nutrient status, seed oil content and water productivity, a two-year experiment at farmers field in Angul, Odisha was taken up. The sunflower yield was found significantly higher with wastewater irrigation (10%) which was mainly contributed by higher head diameter (15.3 cm), no. of achenes per head (467) and 100 achene weight (69g). Similarly, toria crop irrigated with wastewater had higher yield by 11% resulting from higher siliquae per plant (179), no of seeds per siliqua (12.1) and test weight (4.6) compared to freshwater irrigation. Besides this soil nutrients and oil content was higher in wastewater irrigated toria and sunflower crop than freshwater crops. Benefit cost ratio was higher in wastewater irrigated sunflower (3.9) and toria (2.0) crop compared to freshwater irrigated crops (3.0 and 1.4 respectively for sunflower and toria). Water productivity under wastewater irrigation in sunflower (0.38 kg/m3) and toria (0.21 kg/m3) was higher than freshwater irrigated crops by 10-12%. The findings of the present study suggest that wastewater can be used as a source of irrigation for oilseed crop in Angul Odisha where water scarcity is acute during rabi season.