In calcareous soils, wheat productivity is much lower due to improper nutrient management, especially phosphorus (P). Therefore, this study was conducted to manage P availability from various organic (Control, FYM and Sugar cane straw applied at the rate of 10 ton ha−1) and inorganic (Control, 100% rock phosphate (RP), 50% acidulated RP, 100% acidulated RP, single super phosphate (SSP) and diammonium phosphate (DAP)) sources applied at the rate of 90 kg P2O5 ha−1 in calcareous soil while using wheat as test crop. When averaged across the organic sources, SSP performed better in emergence m−2 (126), tillers m−2 (431), spikes m−2 (419), grains spikes−1 (61), plant height (95.1 cm), 1000-GW (40 g), biological yield (11,023 kg ha−1), grain yield (4022 kg ha−1), phosphorus use efficiency (10.5%), phosphorus in leaves at tillering (2.63 mg kg−1) and anthesis stage (2.50 mg kg−1), soil P at heading (1.73 mg kg−1) and post-harvest stage (1.56 mg kg−1) compared to the rest of the mineral sources. Similarly, among the organic sources, FYM performed better than others for all tested traits. Integration of inorganic P sources with organic manures further improved crop performance and post-harvest soil P content. Therefore, using 10 tons FYM ha−1 in integration to SSP or 100% acidulated RP at the rate of 90 kg P2O5 ha−1 is recommended for ensuring optimum wheat productivity under calcareous soils.

A research study was established at the research farm of the University of Agriculture, Peshawar during winter 2018–2019. Commercial biochars were given to the experimental site from 2014 to summer 2018 and received 0.95, 130 and 60 tons ha−1 of biochar by various treatments viz., (Biochar1) BC1, (Biochar2) BC2, (Biochar3) BC3 and (Biochar4) BC4, respectively. This piece of work was conducted within the same study to find the long-term influence of biochar on the fertility of the soil, fixation of N2, as well as the yie1d of chickpea under a mung–chickpea cropping system. A split plot arrangement was carried out by RCBD (Randomized Complete Block Design) to evaluate the study. Twenty-five kilograms of N ha−1 were given as a starter dosage to every plot. Phosphorous and potassium were applied at two levels (half (45:30 kg ha−1) and full (90:60 kg ha−1) recommended doses) to each of the four biochar treatments. The chickpea crop parameters measured were the numbers and masses of the nodules, N2 fixation and grain yield. Soil parameters recorded were Soil Organic Matter (SOM), total N and mineral N. The aforementioned soil parameters were recorded after harvesting. The results showed that nodulation in chickpea, grain yield and nutrient uptake were significantly enhanced by phosphorous and potassium mineral fertilizers. The application of biochar 95 tons ha−1 significantly enhanced number of nodules i-e (122), however statistically similar response in terms of nodules number was also noted with treatment of 130 tons ha−1. The results further revealed a significant difference in terms of organic matter (OM) (%) between the half and full mineral fertilizer treatments. With the application of 130 tons ha−1 of biochar, the OM enhanced from 1.67% in the control treatment, to 2.59%. However, total and mineral nitrogen were not statistically enhanced by the mineral fertilizer treatment. With regard to biochar treatments, total and mineral N enhanced when compared with the control treatment. The highest total N of 0.082% and mineral nitrogen of 73 mg kg−1 in the soil were recorded at 130 tons ha−1 of biochar, while the lowest total N (0.049%) and mineral nitrogen (54 mg kg−1) in the soil were recorded in the control treatment. The collaborative influence of mineral fertilizers and biochars was found to be generally non-significant for most of the soil and plant parameters. It could be concluded that the aforementioned parameters were greater for treatments receiving biochar at 95 tons or more per hectare over the last several years, and that the combination of lower doses of mineral fertilizers further improved the performance of biochar.

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As a multi-beneficial amendment, biochar is very useful to be applied for improving soil health and crop productivity. Therefore, this study was carried out to assess the influence of wood biochar and mineral nitrogen (N), phosphorus (P) and potassium (K) fertilisers viz, [(control; 100% NPK (120:90:60 kg ha−1); 75% NPK + 5 tonne biochar; 50% NPK + 10 tonne biochar; 25% NPK + 15 tonne biochar and 20 tonne biochar ha−1)] on wheat yield and soil properties under different management practices [(raised bed (more than 30 cm above the ground) and flat-bed)]. Split plot two factors randomised completed block (RCB) design with three replications were used where management practices were placed to main plot, while treatments were assigned to subplots. Maximum spike length, grain per spike, 1000 grain weight, grain and biological yield were obtained with application of 75% NPK + 5 tonne biochar ha−1 under both raised and flat-bed, which were statistically at par to 50% NPK + 10 tonne biochar ha−1. The grain and biological yield observed at 75% NPK + 5 tonne biochar and 50% NPK + 10 tonne biochar ha−1 were significantly higher than that of 20 tonne biochar ha−1. However, maximum soil organic matter, extractable P and K contents with slight increases in soil pH and EC was observed at 20 tonne biochar ha−1. Moreover, almost all agronomic parameters were significantly better in raised bed compared to flat-bed sowing. Hence, the present study suggested that 75% NPK + 5 tonne biochar ha−1 is suitable for improving wheat yield and soil properties.

Boron (B) deficiency is a widespread problem in alkaline soils which affects yield and quality of potato but is often ignored by the growers. That’s why, we compared the impact of different methods of boron application (foliar spray, fertigation and soil dressing) along with control on boron use efficiency (BUE), quality and yield of potato in alkaline soils. Boron (0.5 kg ha-1) applied as a foliar spray had significantly increased plant height, tuber per plant, tuber volume and enhanced the quality in terms of vitamin C, starch and B content of potato compared to other methods. Moreover, foliar applied B significantly improved B uptake and it use efficiency over other application methods. B concentration in tubers were strongly correlated with vitamin C and starch contents. The application methods were ranked as foliar spray>fertigation>soil dressing in term of their effectiveness towards potato yield and quality improvement. Thus, for optimum production of good quality potato, B should be applied as foliar spray at the rate of 0.5 kg B ha-1 in existing agro-climatic conditions.