Response of soybean (Glycine max), toria (Brassica compestris) and Indian mustard (Brassica juncea) to supplemental irrigation through harvested rainwater in Central India

Abstract

A field experiment was conducted during 2002-03 to 2004-2005 in red soils to explore the possibilities of rain water harvesting through a farm pond for providing supplemental irrigation to soybean, toria and Indian mustard for increasing growth, yield and water use efficiency. Harvested rainwater was available for supplemental irrigation in farm pond from middle of August to end of October during all the years. Growth and yield attributes of soybean (plant height, number of primary and secondary branches/plant, pods/plant, pod length, number of seed/pod, seed weight/plant and 1000-seed weight), toria and Indian mustard (plant height, number of primary and secondary branches/plant, number of siliqua/plant, siliqua length, number of seed/ siliquae, seed weight/plant and 1000-seed weight) increased with supplemental irrigation which in turn increased the yield of the crops during all the years. Yield of soybean and toria increased by 31 and 138% with supplemental irrigation given at pod filling and 30 days after sowing, respectively over no irrigation. Yield of Indian mustard increased by 91% with one pre-sowing irrigation, and by 343% with pre-sowing + irrigation at branching stage, over rainfed crop. Water use efficiency of all the crops increased with supplemental irrigation. The water use efficiency of soybean and toria increased by 15 and 37% with supplemental irrigation at pod filling and at 30 days after sowing, respectively, over no irrigation. The water use efficiency of Indian mustard also increased by 25 and 45% with pre-sowing and pre-sowing + irrigation at branching stage, respectively, over no irrigation. The results suggested that the productivity of large rainfed areas in the country could considerably be increased even in red soils through rainwater harvesting and providing supplemental irrigation at critical stages of crop growth from a farm pond to some of the selective crops such as soybean during kharif season further available water can also be utilized for providing pre-sowing/supplemental irrigation to post monsoon/rabi season crops such as toria or Indian mustard for increasing the growth, yield and water use efficiency in semi-arid conditions.