Growth and yield of wheat (Triticum aestivum) as influenced by irrigation scheduling and organic manures under Semi-arid Eastern Plain Zone of Rajasthan

A field experiment was conducted under loamy sand soil during the winter (rabi) seasons of 2014–15 and 2015–16 at Jobner, Rajasthan, to study the effect of irrigation scheduling and organic manures on growth and yield of wheat (Triticum aestivum L.). The treatments, consisting of 5 irrigation scheduling, i.e. I1 (irrigation at critical stages), I2 [0.9 irrigation water: cumulative pan evaporation (IW: CPE) ratio], I3 (0.6 IW: CPE ratio at vegetative phase + 0.8 IW: CPE ratio at reproductive phase), I4 (0.6 IW: CPE ratio at vegetative phase + 1.0 IW: CPE ratio at reproductive phase) and I5 (0.8 IW: CPE ratio at vegetative phase + 1.0 IW: CPE ratio at reproductive phase) in main plots, and 4 organic manures [control, FYM @ 15 t/ha, vrmicompost (VC) @ 6 t/ha and FYM @ 7.5 t + VC @ 3 t/ha] in subplots, were replicated 4 times in split-plot design. The pooled mean results showed that irrigation applied at an 0.9 IW: CPE ratio (I2) recorded the maximum values of growth parameters (dry-matter accumulation and functional leaves) and yield (grain, straw, biological and harvest index) proved significantly superior to I1, I4 and I3. However, the treatment I5 with maximum plant height also remained equally effective with regard to above parameters. With regard to relative water content and total number of tillers the above treatment being at par with I1 proved superior to rest of the treatments. Results further indicated that application of FYM at 7.5 t + VC at 3 t/ha (M3) resulted in significantly higher growth parameters (plant height, dry-matter accumulation and total number of tillers), yield (grain, straw, biological and harvest index) and being at par with M2 (VC at 6 t/ha) proved superior to rest of the treatments. However, the above treatment (M3) recorded significantly higher functional leaves and relative water content (RWC) over M0 (Control) and M2. Scheduling of irrigation to wheat either at 0.9 IW: CPE ratio throughout the growth or 0.8 IW: CPE ratio at vegetative phase + 1.0 IW: CPE ratio at reproductive phase resulted in significantly, higher yield (grain, straw and biological). Irrigating the crop with 0.8 IW: CPE ratio at vegetative phase + 1.0 IW: CPE ratio at reproductive phase was found most effective, as this schedule besides resulting in almost equal yields also curtailed 1 irrigation with the highest water-use efficiency. The treatment combination, I2M3 recorded the significantly higher grain yield over rest of the treatment combinations except I2M2, I5M2 and I5M3.