Enhancing productivity of summer gum guar (Cyamopsis tetragonoloba) through irrigation and fertilization on sandy loam soils of Gujarat

A field experiment was conducted during the summer seasons of 2013 and 2014 on sandy loam soils to evaluate levels of irrigation and fertilization in gum guar [Cyamopsis tetragonoloba (L.) Taub.] at Junagadh Agricultural University, Nana-Kandhasar, Surendranagar, Gujarat. The treatments comprising of four levels each of irrigation (0.4, 0.6, 0.8 and 1.0 IW: CPE ratios) and fertilization (00–00, 10–20, 20–40 and 30–60 kg N-P₂O₅ ha⁻¹) were tested using split plot design with three replications. The pooled results indicated that irrigation at 0.8 IW:CPE enhanced the growth parameters viz., plant height, number of branches, number and dry weight of root nodules, dry matter plant⁻¹ and leaf area index, yield attributes viz., number of pods plant⁻¹, number of seeds pod⁻¹, pod length, 1000-seed weight and shelling per cent along with seed yield, stover yield and harvest index with higher net returns of Rs. 53895 ha⁻¹ and B:C ratio of 2.29 over 0.4 IW:CPE ratio. The maximum consumptive use of water was noticed under 1.0 IW: CPE ratio, while the maximum water use efficiency and water expense efficiency were persisted under 0.4 IW: CPE. Application of 20–40 kg N-P₂O₅ ha⁻¹ promoted growth parameters viz., plant height, number of branches, number and dry weight of root nodules, dry matter plant⁻¹, leaf area index, yield attributes viz., number of pods plant⁻¹, number of seeds pod⁻¹, pod length, 1000-seed weight and shelling per cent along with seed yield, stover yield and harvest index with higher net returns of Rs. 52967 ha⁻¹ and B:C ratio of 2.24 than control. The maximum consumptive use of water, water use efficiency and water expense efficiency were noticed under 30–60 kg N-P₂O₅ ha⁻¹.