Optimizing Irrigation Water Scheduling of Sugarcane Planted Under Furrow Method with Trash Mulch Combinations for Enhancing Cane Productivity and Water Use Efficiency

A field trial was conducted at the Sugarcane Research Station, Nayagarh (Odisha), during 2016–2017, 2017–2018 and 2018–2019 cropping seasons with the objectives of optimizing irrigation water scheduling of sugarcane planted under furrow method with trash mulch incorporation for enhanced water use efficiency and sugarcane productivity in the tropical monsoon type coastal climatic conditions of Odisha. Standing on the coastal belt, the weather in Odisha is greatly influenced by the sea. The soil of the experimental field was sandy loam in texture, slightly acidic (pH-6.3) in reaction with low-organic carbon content (0.481%) and available N status (240 kg/ha) besides medium in available P (11.2 kg/ha) and K (137 kg/ha). The experiment was laid out in strip plot design keeping furrow method of sugarcane planting under trash mulch combinations in horizontal block and irrigation scheduling in vertical block with three replications taking sugarcane variety CoOr 12346 as a planting material. The results of the trial revealed that furrow method of planting (120 cm apart) with trash mulching produced significantly higher number of millable canes (NMC) and cane yield of 88.75,000/ha and 104.472 t/ha, respectively, which was statistically at par with furrow method of planting (120 cm apart) with alternate skip furrow irrigation after earthing-up + trash mulching. Irrigating the crop at irrigation water/cumulative pan evaporation (IW/CPE) ratio of 1.0 produced significantly higher NMC and cane productivity of 87.68,000/ha and 103.424 t/ha, respectively, than that of the crop irrigated at IW/CPE ratio of 0.6 (NMC and cane yield of 81.82,000/ha and 91.858 t/ha, respectively). However, irrigating the crop at 0.8 IW/CPE ratio produced statistically at par NMC and cane yield with that obtained from irrigating the crop of sugarcane at 1.0 IW/CPE ratio. Maximum water use efficiency was recorded with IW/CPE of 0.6 (829.8 kg/ha-cm) followed by IW/CPE ratio of 0.8 (745.5 kg/ha-cm). Furrow planting (120-cm row spacing) with alternate skip furrow irrigation after earthing-up + trash mulching treatment recorded higher water use efficiency (819.6 kg/ha-cm) with less quantity of irrigation water applied (112.8 cm) than that of other combinations under this planting method. Alternate skip furrow irrigation with mulching saved irrigation water by 35.3% besides increasing water use efficiency by 14.6% as compared to every furrow irrigated sugarcane without mulching. Thus, alternate skip furrow irrigation with trash mulch proved to be an effective moisture conservation practice to minimize wastage of irrigation water.