Influence of irrigation regimes and nitrogen levels on aerobic rice during summer season

A field experiment was carried out on aerobic rice during summer season of 2013 and 2014 at Regional Research and Technology Transfer Station, Chiplima, Sambalpur, Odisha in order to find out the most remunerative irrigation regimes and nitrogen levels in aerobic rice for higher yield, water use efficiency and economics. The experiment was laid out in split plot design with 3 replications. Main plot treatments consist of four irrigation regimes (irrigation at 3 days interval, 5 days interval, 7 days interval and 9 days interval) and in subplot treatments consist of four levels of nitrogen (no nitrogen, 40 kg ha-1, 60 kg ha−1 and 80 kg ha−1). The pooled mean result revealed that decreasing irrigation interval increased the values of growth and yield attributes, grain yield and B: C ratio. Irrigation at 3 days interval with regards to growth and yield attributes was significantly superior to rest other higher irrigation interval. Whereas in grain yield and B: C ratio, irrigation at 3 days interval was at par with irrigation at 5 days interval and significantly superior to rest other higher irrigation interval. However, field water use efficiency was maximum at 7 days interval which was at par with 5 days interval. The application of nitrogen at 80 kg ha−1 recorded significantly higher yield attributes, grain yield, field water use efficiency and B: C ratio than rest other lower levels of nitrogen.