Optimization of nitrogen application and irrigation schedules in tuberose (Polianthes tuberosa Lin.) was tested. Maximum vegetative growth and spike production in tuberose was observed in treatment receiving nitrogen @ 320 kg ha−1, which increased number of florets spike−1 and bulb yield (tha−1) by 40% & 69%, respectively over control. However, maximum nitrogen use efficiency was registered to be 25.42% in the treatment receiving nitrogen @ 120 kg ha−1 followed by 17.7% in @ 220 kg ha−1 and 13.93% in treatment receiving N @320 kg ha−1. Irrigation applied at 0.8 IW/CPE ratio increased number of florets spike−1 and bulb yield (t ha−1) by 23% & 22% over control (flood irrigation) and by 30% & 44%, respectively as compared to minimum water receiving treatment at 0.4 IW/CPE ratio. Water productivity based on consumptive use (WPCU), irrigation water (WPIR) and total water (WPTW) includes applied water through irrigation and rainfall improved vegetative growth, spike and bulb yield appreciably with increasing ratio of water application from 0.4 to 0.8 IW/CPE ratio but failed to increase beyond 0.8 IW/CPE ratio which indicates that water application beyond 0.8 IW/CPE ratio is not being utilized by crop. Water productivity based on consumptive use (WPCU) increased by 70% (0.40 g. dry matter in florets kg−1 of water) in 0.8 IW/CPE over control (0.23 g. dry matter in florets kg−1 of water). Irrigation through drip system at 0.8 IW/CPE ratio saved water by 39% and increased dry matter in florets by 45% as compared to traditional flood method.
Irrigation, IWI CPE ratio, Nitrogen use efficiency, Spike quality and Tuberose
