Effect of irrigation levels, crop geometry and mulching on yield, economics and water use efficiency of fennel (Foeniculum vulgare Mill.) grown under drip system in Western Rajasthan, India

A study was carried out at Swami Keshwanand Rajasthan Agricultural University, Bikaner, Rajasthan, during the rabi seasons of 2015–16 and 2016–17 to investigate the effects of irrigation levels, crop geometry, and mulch on yield parameters, yield, economics, and water use efficiency of fennel (Foeniculum vulgare Mill.). Findings showed that the irrigation level of 0.8 ETc considerably increased the yield parameters of fennel, including seed (1684 kg ha-1) and stover yield (3110 kg ha-1), net return (103149 ha-1) and benefit: cost ratio (2.58). At 0.6 ETc, a maximum water use efficiency of 5.48 kg ha-1 mm-1 was observed. 40 cm x 60 cm paired row planting produced significantly superior yield parameters, seed yield, and water use efficiency. Results further revealed that the application of plastic mulch considerably improved yield parameters, yield, net return, and benefit: cost ratio as compared to no mulch treatment. However, test weight and harvest index were not influenced by plastic mulch. Thus, in arid and semi-arid parts of Rajasthan, integrated use of drip irrigation at 0.8 ETc and plastic mulch under paired row sowing of 40 cm x 60 cm proved more viable for ensuring higher productivity of rabi fennel.