Drip irrigation and fertigation improve economics, water and energy productivity of spring sunflower (Helianthus annuus L.) in Indian Punjab

A field experiment was conducted to find out water and energy efficient irrigation and fertigation schedule for higher profitability from spring sunflower during 2014 and 2015. The experiment was laid out in randomized complete block design keeping combinations of three drip irrigation {(100, 80 and 60% of crop evapotranspiration (ETc)} and three fertigation schedules {(100, 80 and 60% of recommended dose of fertilizers (RDF) i.e. 60 kg N and 30 kg P2O5ha−1)} with an extra absolute control treatment (furrow irrigation and manual application of RDF). The seed yield of sunflower was statistically at par between drip irrigation at 100 and 80% ETc but significantly better than 60% of ETc. However, apparent water productivity (AWP) and energy productivity was higher in drip at 80% ETc than 100 or 60% ETc. The crop drip irrigated at 80% ETc produced 397 g more seed yield with each cubic metre of irrigation water applied at yield advance and water saving of 27.8 and 33.3% than absolute control, respectively. Among the fertigation schedules, seed yield, oil yield and AWP were significantly higher from 100% RDF than 80 or 60% RDF and similar trend was observed for net returns and energetics. Drip irrigation either at 100% of ETc or 80% ETc with 100% of RDF or 80% of RDF produced significantly higher seed yield, net returns and energy productivity than absolute control. Thus, drip irrigation at 80% of ETc with 80% of RDF is more economically viable with higher water and energy productivity than absolute control.