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Integrated nutrient management is an approach where judicious application of chemical fertilizers is used together with organic manures and biofertilizers for sustainable production. Lettuce and Chinese cabbage were studied in separate experiments under shade-house conditions with reduced levels of chemical fertilizers (50 and 75% of the recommended dosage) along with organic manures including farmyard manure (FYM) and vermicompost (VC) and biofertilizers including azotobacter and phosphorus-solubilizing bacteria (PSB) in 2015 at the Hi-Tech Horticulture Unit, University of Agricultural Sciences, Dharwad, India. Crops were raised on soil media with drip irrigation. The experiment on lettuce revealed that the treatment comprising 75% RDF + FYM and VC at 1:1 ratio equivalent to 25% recommended dose of nitrogen (RDN) + azotobacter + PSB gave significantly higher leaf yield plant(-1) (300.15 g), yield ha(-1) (27.00 t) and benefit:cost (B:C) ratio (3.05), which was on par with the treatment with 50% RDF + FYM and VC in 1:1 ratio equivalent to 50% RDN + azotobacter + PSB, which resulted in leaf yield of 295.35 g plant(-1), 26.50 t ha(-1) and B:C ratio of 3.37. Similarly, in Chinese cabbage, the treatment with application of 75% RDF + FYM and VC in 1:1 ratio equivalent to 25% RDN + azotobacter + PSB recorded significantly higher head yield per plant (1850 g), yield ha-1 (64.70 t) and B:C ratio (3.28) and it was on par with the treatment combination of 50% RDF + FYM and VC in 1:1 ratio equivalent to 50% RDN + azotobacter + PSB, which recorded a head yield of 1725 g plant-1, 60.30 t ha(-1) and B:C ratio of 3.57.

An experiment was carried out during 2014-15 to study the fruit yield and quality of bell pepper grown under a naturally ventilated polyhouse with three irrigation regimes [I(1): 40, I(2): 60 and I3: 80% of crop evapotranspiration (ETc)] and three fertigation levels (F(1): 50, F(2): 75 and F(3): 100% of recommended dose of fertilizers) along with a control (drip irrigation at 100% ETc + soil application of fertilizers). Daily measured outside evaporation ranged from 1.9 to 14.4 mm day-1 during cropping season. Cumulative water requirements under the different irrigation regimes were 793, 635, 476 and 317 mm for 100, 80, 60 and 40% of ETc, respectively. Irrigation replenishment at 60 and 80% of ETc were at par with significantly higher fruit yield (8.10 and 8.16 kg m(-2), respectively), moisture content (92.84 and 93.05%) and crude fibre (2.33 and 2.28%). The maximum total dietary fibre content (2.50%) occurred under 60% of ETc. Ascorbic acid (171.46 mg 100 g(-1)) and total soluble solids (5.38 °Brix) contents were significantly highest at 40% of ETc irrigation regime. Among the fertigation levels, F(2) (75%) and F3 (100%) were at par with regard to fruit yield and most of the quality parameters. All the interactions of I×F outperformed the control with respect to fruit yield and the majority of the fruit quality parameters. From this study, it is concluded that the combination of irrigation replenishment at 60% of ETc and fertigation with 75% recommended fertilizer dose (I(1)×F(2) was optimal for obtaining a higher yield in bell pepper with better qual)ity fruits, along with savings of 40% of irrigation water and 25% of fertilizers.