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Balanced nutrient application is an important concern to minimize fertilizer use in crop culture. Field experiments were conducted during kharif 2017 and 2018 to find out the best level of NPK fertilizer for rice with two varieties of rice of same duration (130-135 days). Three grades of customized fertilizers (250, 350 and 450 kg ha À1 ) along with 100% RDF (Recommended dose of fertilizer) and absolute control constituted the treatment variables. The results revealed that the grades of customized fertilizer (CF) influenced the yield and uptake of nutrients. Application of CF @ 450 kg ha À1 was found to be significantly superior over absolute control and 100% RDF with respect to yield and uptake of nutrients, and found on par with all other grades of CF (250 and 350 kg ha À1 ). Applying 250 kg ha À1 of CF recorded higher agronomic efficiency (AE), apparent recovery efficiency (ARE) and partial factor productivity (PFP) for phosphorus (P) and potassium (K) but higher AEn, AREn and PFPn in 450 kg ha À1 of CF. The higher utilization efficiency of nitrogen (UEn) of 43.05%, phosphorus (UEp) of 181.88% and potassium (UEk) of 34.40% were recorded in 250 kg ha À1 of CF. The CF @ 450 kg ha À1 recorded higher nitrogen and phosphorus requirement (NR and PR) i.e., 2.65 and 0.61 kg's, respectively. Whereas, potassium requirement (KR) was higher in 100% RDF. Higher response yard stick (RYS) of 5.33 was recorded in 250 kg ha À1 of CF compared to other grades of CF, 100% RDF and absolute control.

A study was conducted to characterize soil salinity and sodicity of Ghataprabha Left Bank Canal command area of Mudhol taluk (Bagalkot District). Bulk Electrical conductivity of salt affected soils was determined by using electromagnetic induction (EM 38). The pHs of surface and sub-surface soil layers ranged from 7.4 to 8.7 and 7.7 to 8.6, respectively. Electrical conductivity of saturated extract of surface and sub-surface soils ranged from 4.2 to 59.9 dSm -1 and 4.2 to 57.0 dSm -1 . Majority of soil samples were found to be saline as sodium absorption ratio (SAR) ranged between 0.3 to 10.8 and 0.5 to 10.9 for surface and sub-surface soil, respectively. Among the analysed surface soil samples, 26 per cent were saline, 18 per cent sodic and 56 per cent were saline-sodic. On the other hand, 26, 20 and 54 per cent of soils were categorized into saline, sodic and saline-sodic, respectively. Among the water soluble cations, Na + (10.9 to 73.4 cmol (P + ) kg -1 ) pre-dominated in surface and sub-surface horizons (10.9 to 65.2 cmol (P + ) kg -1 ). Among water soluble anions, Cl -dominated both in surface (2.0 to 60 me L -1 ) and sub-surface (2.0 to 59.0 me L -1 ).

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