Delayed irrigation: An approach to enhance crop water productivity and to investigate its effects on potato yield and growth parameters

Highly efficient irrigation and conservative sowing practices are required at the farm level for sustainable crop production. For the purpose, a field experiment on autumn potato crop was conducted during the years 2014–15 and 2015–16 to maximize crop water productivity. Five treatments with two sowing configurations were designed i.e. ridge sowing under furrow irrigation (RF), bed sowing under furrow irrigation (BF), and three drip irrigation treatments for different Management Allowed Depletion (MAD) levels under bed sowing i.e. irrigation when 20% (DIR1), 35% (DIR2), and 50% (DIR3) of the available plant water depleted from the soil. Results revealed that drip irrigation treatments influenced potato yield (P ≤ 0.05), the highest yield during both the years were recorded in the control treatment (RF) measured as 49.65 and 42.55 tons ha−1 respectively. The maximum number of total potato tubers m−2 were found in treatment DIR2 while control treatment (RF) was at par of others in terms of marketable tubers. The maximum percentage of green (3.81, 3.75), rotten (2.95, 2.20), damaged (2.10, 2.87), and cracked (2.33, 1.79) tubers were observed in ridge sowing under furrow irrigation (RF) during both years of experiment. The maximum water saving was achieved by 50.33% and 42.66% in DIR3 as compared to control one (RF) whereas maximum crop water productivity in kg m−3 was achieved in DIR2 (i.e. 13.01, 13.60) during the first and second year of experiment respectively. In conclusion, bed planting under furrow and drip irrigation treatments proved superior to control practice (RF) in terms of water saving, water productivity, total number of tubers, and different other plant growth parameters. However, further studies on nutrient management are recommended for the bulking of non-marketable tubers in bed planting method which ultimately enhances yield and net return to the farmers.