Production potential, water-use efficiency and economics of hybrid rice under different levels of irrigation and weed management practices

The effect of irrigation levels and weed management practices on yield, yield components, water-use efficiency and economics of hybrid rice (cv. Pro Agro 6444) was studied. The results revealed that continuous submergence of 5  2 cm with weed free check (at fortnight interval) showed maximum grain yield (8.22 t ha-1) and yield attributes. Continuous submergence with unweeded control consumed maximum water (153 cm) and lowest water-use efficiency (4.02 kg ha-1 mm-1), while irrigation (5 cm) at 3 days after disappearance of ponded water with weed free check gave the maximum water-use efficiency (16.31 kg ha-1 mm-1). The maximum net return (Rs.33,565 ha-1) was obtained under continuous submergence with weed free check, however, the benefit: cost ratio (1.94) was highest under continuous submergence with pre-emergence application of Pyrazosulfuron ethyl 10% WP @ 25 g ha-1 at 7 days after transplanting.