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In Indian mustard and wheat, newly developed phosphorus fertilizers, Suphla of 20:20:0 grade with 60 and 80% water solubility were comparable with di‐ammonium phosphate for crop productivity. Residual effect of newly developed phosphorus fertilizers sources was significant in succeeding maize and soybean crops. All P sources were found equally effective and recorded higher yields and nutrient uptake compared to omission of P. Phosphorus fertilizer sources, Suphla of 20:20:0 grade with 60 and 80% water solubility can be used to meet out the P requirement of mustard–maize and wheat–soybean systems. Crop responses to P fertilization, in terms of productivity, phosphorus‐use efficiency (PUE), and residual fertility in soil, can depend on the form of P applied. A field experiment was conducted to determine the effect of various P fertilizer forms on productivity and PUE indices in two predominantly practiced Indian mustard [Brassica juncea (L.) Czern & Coss.]–maize [Zea mays (L.)] and wheat [Triticum aestivum (L.) emend. Flori & Paol]–soybean [Glycine max (L.) Merrill] cropping rotations. The experiment was conducted during 2012–2014 at the Indian Agricultural Research Institute, New Delhi, India. A ‘Suphala’ P fertilizer, with 30, 60, and 80% water solubility was compared with single superphosphate (SSP) and di‐ammonium phosphate (DAP), all including the recommended dose of N and K through urea and muriate of potash. The seed yield (6.0—21.3%), crop equivalent yield (4.7–10.3%) and system net returns (1.8–11.8%) of Indian mustard were higher with direct application of SSP over other soluble and partially soluble P fertilizers. Wheat yield (4.6–9.6%) and system net returns (2.7–9.6%), were higher using DAP. However, the residual effect of P fertilizers exerted a significant influence on the performance of succeeding maize and soybean crops. Using DAP as P fertilizer form recorded higher grain yield and system net returns of maize and soybean than other soluble P forms. Irrespective of the fertilizer form, treatments involving P application improved P use indices, and apparent N and K recovery in Indian mustard and wheat crops. Hence, the studied P fertilizer forms will result in higher productivity, sustainable use of resources and reduction in production costs for these cropping systems.

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Intensive farming with high yielding cultivars, application of high analysis NPK fertilisers, and reduced use of organic manures caused a decrease in the availability of zinc (Zn) in Indian soils. We collected soil and plant samples from an ongoing long-term experiment at Indian Agricultural Research Institute, New Delhi, to study the distribution of different fractions of Zn in an Inceptisol and their contribution towards the Zn availability in soil and Zn uptake in maize–wheat crop rotation. The treatments used for the study were NPK, NPK + FYM, NPK + Zn, and control (no fertiliser or manure). The DTPA-Zn concentration in soil was higher where Zn had been applied and declined with an increase in soil depth. The distribution of different fractions of Zn under various treatments and depths was inconsistent, and varied in a cropping year. The average concentration of total Zn (mg/kg) was 183, 183, 171, and 211 in 0–0.15, 0.15–0.30, 0.30–0.45, and 0.45–0.60 m depth, respectively. Residual Zn was the dominant portion of total Zn at all soil depths. Grain and stover yield of maize ranged from 1.10 to 2.43 t/ha and 1.22 to 2.46 t/ha, respectively, under different treatments, whereas, the yield of wheat grain varied from 2.25 to 4.69 t/ha and that of wheat straw from 2.56 to 5.20 t/ha. Highest uptake of Zn by both the crops occurred in Zn-treated plots. Zinc associated with easily reducible manganese, carbonate and iron and aluminum oxides contributed directly towards DTPA-extractable Zn. Sorbed Zn (SORB-Zn) and Zn associated with organic matter (OM-Zn) contributed significantly towards Zn uptake by the 2 crops.