When water supplies are restricted, so that full evapotranspiration demands cannot be met, limited irrigation is practised. Management strategy of limited irrigation is to optimise production per unit of applied water rather than to maximise yield per unit of land. Principles that help to facilitate limited irrigation strategies can be broadly grouped into three: agricultural water management, crop considerations and agronomic options. When anticipating low water year, choose crops which maximise production with limited water. In decreasing order of efficiency, short season indeterminate and long season indeterminate crops should be chosen judiciously. Deficit irrigation practices, localised irrigation methods, reducing water losses,conjunctive use of water resources etc can help minimise yield losses due to soil moisture stress. Additional agronomic management options that can maximise production include conservation tillage, advancing or delaying planting dates in order to coincide the crop’s critical period with water availability, decreasing plant competition byreducing seeding density and controlling weeds. Available options to address the challenge of limited irrigation have been briefly presented.

A field experiment was conducted to optimise the organic, inorganic and biofertiliser needs for sustained productivity of maize (Zea mays L.). Seven treatments comprising all possible combinations of chemical fertilizer, organic manure (vermicompost, FYM) with and without biofertilizer (Azospirillum and PSB) were laid out in randomized block design with three replications. Different nutrient management practices (organic, inorganic and combined sources of nutrients) significantly influenced the yield attributes, yield and economics of maize crop. Application of 100 % RDF (T1:180-60-50 kg N, P2O5 and K2O ha -1 ) resulted in significantly higher cob length, girth (17.7 cm, 16.8 cm), cob weight (225 g), no. of kernel rows cob -1 (12.9), no. of kernels row -1 (24.2), kernel weight cob -1 (5207 kg ha -1 ), kernel yield (5207 kg ha -1 ) and stover yield (6751 kg ha -1 ) which was significantly superior over the rest of the nutrient management practices and it was followed by 50% RDF + Vermicompost @ 1t ha -1 + Azospirillum @ 5 kg ha -1 + PSB @ 5 kg ha -1 (T7) and it has given a remarkable yield attributes, kernel (4683 kg ha -1 ) and stover yield (6394 kg ha -1 ) which is in turn in parity with 50% RDF + FYM @ 5 t ha -1 + Azospirillum @ 5 kg ha -1 +PSB @ 5 kg ha -1 (T6) and significantly superior to rest of the treatments. The highest net returns (₹ 59920 ha -1 ) and benefit -cost ratio (2.97) were recorded under 100% RDF (T1) followed by application of FYM @ 10 t ha -1 + Azospirillum @ 5 kg ha -1 + PSB @ 5 kg ha -1 (T6) which has registered a B:C ratio of 2.81 which might be due to comparatively better increase in yield with lesser cost over other treatments. Integration of biofertilizer (T6 and T7) has triggered the nutrient uptake mechanism and shown a notable performance in improving yield structures, yield and economics. Long run adoption of combined use of fertilizers and organics expected to match and even excel the sole fertilizer based production strategy.

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