Influence of sowing dates and irrigation schedules on growth and yield of drip irrigated wheat (Triticum aestivum) under semi-arid conditions of Punjab

A study was conducted during the winter (rabi) seasons of 2014–16 at Ludhiana, Punjab, to evaluate the influence of sowing time and drip-irrigation schedules on growth and yield of wheat (Triticum aestivum L.). The experiment was conducted in a split-plot design consisting of 4 sowing dates (D₁, 25 October; D₂, 10 November, D₃, 25 November and D₄, 10 December) in main plots and 5 irrigation treatments in subplots, replicated thrice. Four irrigation treatments based on soil water deficit from field capacity, were: 15% depletion (FC₁₅); 25% depletion (FC₂₅); 35% depletion (FC₃₅); and 45% depletion (FC₄₅) from field capacity (FC) and the fifth irrigation treatment was taken as conventional practice (CP). The results revealed that plant height, dry-matter accumulation, leaf-area index and number of tillers decreased significantly with delay in sowing from D₁ to D₄ at all stages of plant growth. The grain and biological yields were significantly higher in D₁ than the other sowing dates. The pooled grain and biological yields decreased by 9 and 8% from D₁ to D₂, 18 and 17% from D₁ to D₃ and 29 and 27% from D₁ to D₄ respectively. Significantly higher values of growth attributes and yield were recorded with application of irrigation at FC₁₅ than the other irrigation schedules. The pooled grain yield in FC₁₅ treatment was higher by 9, 25, 42 and 10% than FC₂₅ FC₃₅, FC₄₅ and CP respectively. Thus, irrigating the crop at FC₁₅ using drip irrigation saved 50% irrigation water as compared to the conventional practice of irrigating the crop at 4–5 week interval with 75 mm of water.