A field experiment was conducted during winter ( rabi) season of 2005-06 and 2006-07 in the Agronomy Research Farm of Amar Singh College, Lakhaoti, Uttar Pradesh to study the effect of levels of irrigation and fertility on chickpea ( Cicer arietinum L.) and mustard ( Brassica juncea L. czernj & coss.) in sole and intercropping systems. The experiment was conducted in split-plot design with 3 replications. The combination of treatments consisted of 3 cropping systems, namely sole mustard (C 1), sole chickpea (C 2) and chickpea+mustard intercropping (C 3) (4:1 raw ratio) and 4 irrigation levels [no irrigation (I 0), irrigation at pre-flowering (I 1), at pod formation (I 2) at both pre-flowering and pod formation (I 3)] for chickpea allotted to main plots and 3 fertility levels [F 1 (20:40:10 kg N, P 2O 5 and S/ha) F 2 (40:60:20 kg N, P 2O 5 and S/ha) and F 3 recommended dose of fertilisers (RDF)] for both the crops on row length basis to sub-plots. The sole Indian mustard recorded higher seed yield compared to intercropping. The yield reduction in mustard was to the tune of 58.9% and 60.0% in the first and second year, respectively, due to intercropping chickpea. Irrigation, on an average increased the mustard yield by 6.47% (I 1), 12.18% (I 2) and 13.18% (I 3) compared to no irrigation (I 0). Similarly fertilizer treatments F 2 and F 3 on an average increased mustard yield by 10.17% and 18.46%, respectively, over the F 1. The intercropping of chickpea and mustard in 4:1 raw ratio was significantly superior to sole crops of either chickpea or mustard in terms of yield and economics. Between the sole crops, chickpea was better as compared to mustard. Application of recommended dose of fertilizers (20:60:20 kg, N, P 2O 5 and S/ha) on area basis was superior.
