Response of late-sown wheat (Triticum aestivum) to limited irrigation, seed rate and depth of sowing

Abstract

A field experiment was conducted during the winter (rabi) season of 2014–15 and 2015–16 at New Delhi, to study the effect of limited irrigation, seed rate and depth of sowing on growth, yield, water-use parameters and economics of late-sown wheat (Triticum aestivum L.). The experiment comprised 3 factors, viz. 3 irrigation levels [(I1 , irrigation at crown-root initation (CRI) stage; I2 , irrigation at CRI stage + 0.2 irrigation water: cumulative pan evaporation (IW : CPE) ratio; and I3, irrigation at CRI stage + 0.4 IW : CPE ratio), 3 seed rates (S1, 75; S2, 100 and S2, 125 kg/ha) and 2 depths of sowings (D1, 5 cm and D2 , 10 cm). The field experiment comprising 18 treatment combinations, replicated thrice, was laid out in strip-plot design. Interactions between irrigation levels and seed rates, and irrigation levels and depths of sowing for grain yield were significant during 2014–15. Irrigation levels, seed rates and depths of sowing also significantly affected plant height, yield attributes, grain yield, straw yield and harvest index. Irrigation at CRI stage + 0.4 IW : CPE ratio resulted in significantly the highest plant height (86.3 cm), effective tillers/m2 (407.82), spike length (14.40 cm), spikelets/spike (17.43), grains/spike (44.20), grain weight/spike (2.05 g), 1,000-grain weight (48.95 g), grain yield (4.22 and 3.75 t/ha during 2014–15 and 2015–16) and harvest index (0.497 and 0.477 during respective season). Seed rate of 125 kg/ha resulted in significantly the highest plant height (82.7 cm), effective tillers/m2 (416.66), spike length (14.62 cm), spikelets/spike (17.53), grains/ spike (40.20), grain weight/spike (2.06 g), 1,000-grain weight (47.80 g), grain yield (3.63 t/ha during 2015–16) and harvest index (0.496 and 0.456 during respective year). Sowing depth of 10 cm resulted in significantly the highest plant height (82.2 cm), effective tillers/m2 (382.64), spike length (13.94 cm), spikelets/spike (16.44), grains/spike (38.21), grain weight/spike (1.90 g), 1,000-grain weight (46.24 g), grain yield (3.95 and 3.49 t/ha during both the years) and harvest index (0.456 and 0.443 during both the years).