Owing to their high carbon and nitrogen contents, biogas residues may lead to higher carbon dioxide (CO2) and nitrous oxide (N2O) emissions from soils. Acidification of biogas slurry and application of nitrification inhibitors (NIs) could mitigate the emission of these gases. An incubation experiment was therefore carried out to investigate the effect of NIs, DMPP (3, 4-dimethylpyrazole phosphate), and PIADIN (active ingredients: 3.00–3.25% 1,2,4-triazole and 1.50–1.65% 3-methylpyrazole), on CO2 and N2O emissions from soils fertilized with biogas residues and acidified biogas residues. Biogas residues produced higher ammonium-nitrogen (NH4+-N) and nitrate-nitrogen (NO3−-N) concentrations in soils which resulted in higher emissions of CO2-C and N2O-N than that from acidified biogas residues. Both DMPP and PIADIN significantly decreased the emissions of CO2-C (8.1–55.8%) and N2O-N (87–98%) and maintained lower NH4+-N and NO3−-N concentrations when compared to control (without nitrification inhibitors). However, the DMPP had a higher reduction capability for CO2-C emissions than PIADIN in acidified biogas residue applied soil. In conclusion, the acidification of biogas residues and application of NIs are effect in reducing gaseous emission from biogas residue fertilized soils and thus could improve the fertilizer effectiveness of the residues.

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W heat (Triticum aestivum L.) is a staple food and is a leading cereal crop for the entire population and belongs to family Poaceae. Flour of wheat is used for piecrust, bread, biscuit and the vegetative plant parts make valuable livestock feed. During 2014-15, wheat was grown on 9205.5 thousand hectares area and its production was 25.09 million tons in Pakistan (MNFSR, 2014-15). In Khyber Pakhtunkhwa, Pakistan, the area of wheat sown was 732.6 thousand hectare and its production was 1.260 million tons Abstract | Nitrogen application has a significant impact on wheat crop phenology and crop stand. To optimize nitrogen sources i.e. urea, farmyard manure (FYM) and poultry manure (PM) for improving wheat phenology and crop stand, an experiment was conducted at Agriculture Research Station Perdal Khel, Bannu (South part of Khyber Pakhtunkhwa, Pakistan) during 2016-17. The soil of the experimental area was Loamy sand with Haplic yermosols soil series based on FAO classification. The experiment comprised of three tillage practices i.e. Shallow tillage (ST), Conventional tillage (CT) and Deep tillage (DT) and eight nitrogen treatments (Control, 100% Urea, 100% FYM, 100% PM, 50% Urea/FYM, 50% Urea/PM, 50% FYM/PM and 33.33% each PM/FYM/Urea). These ratios provided a total of 120 kg N ha -1 . The wheat cv. Pakhtunkhwa-2015 was sown with seed of 120 kg ha -1 . The CT resulted in early phenology (days to emergence (11.5 days), booting (105 days), anthesis (116 days), and physiological maturity (155 days) whereas, DT delayed the phenological events. Among nitrogen ratios sole use of urea had delayed booting (108.1 days), anthesis (122.9 days) and physiological maturity (162.5 days) stages, whereas different ratios of Urea, FYM and PM resulted in early phenological observations. The use of urea, FYM and PM (33.33% each) had produced more tillers m -2 (288 tiller m -2 ) as compared to sole source or control plots. Conclusively, CT performed better than DT for wheat crop phenology and crop stand. Similarly, Urea, FYM and PM applied in equal ratio improved crop stand whereas sole urea delayed phenology of wheat crop. Thus, it is recommended that 120 kg N ha -1 supplied as 33.3% from urea, FYM and PM combined with CT practice is more favorable production technology to improve crop stand of wheat.

W heat (Triticum aestivum L.) belonging to family Poaceae and utilized for food and feed purpose. Pakistan occupies 8 th position in wheat production (Muhammad et al., 2013). It is cultivated over 42% of total cultivable land in Pakistan with average production of 2919 kg ha -1 (MNFSR, 2018). The average yield of wheat in Pakistan is not satisfactory for the food demands of increasing population. Pakistani nation prefer wheat over the grains crops like rice, maize, barley etc. (Muhammad et al., 2013). This low wheat productivity is being associated with low soil fertility and imbalance use of nutrients.Frequent and continuous supply of nutrients results in improving the yield and yield parameters (Muhammad et al., 2013). Wheat needs huge amount of nutrients including nitrogen, and thus depleting Abstract | The stimulated decomposition of farmyard manure (FYM) through soil amendments is considered to improve the nitrogen (N) availability and hence the crop biomass. With this view, the four soil amendments [i.e. No-amendments, Min-N (30 kg N ha -1 ), humic acid (2.5 kg ha -1 ) and effective microbes (200 L Mg -1 of FYM)] were added to five levels of FYM (i.e. 0, 5, 10, 15 and 20 Mg ha -1 ) and their impact were quantified in terms of wheat phenology, crop stand and biomass during two years studies (2016-17 and 2017-18). Min-N was provided from urea, humic acid from "humic plus" a commercial product having 40% humic acid, and effective microbes from "bioaab" a commercial product having beneficial microbes like bacteria, yeast and actinomycetes. Average over years, the maximum days to anthesis (126 days), physiological maturity (154 days) and enhanced emergence (9 days) were observed with 20 Mg FYM ha -1 . The emergence m -2 (126), leaf area tiller -1 (107 cm 2 ), plant height (96.5 cm) and biomass (11783 kg ha -1 ) were improved with 20 Mg FYM but were non-significantly different from plots having 15 Mg FYM ha -1 over two years averaged data. Among the amendments, greater days to anthesis (126 days) and physiological maturity (154 days) was noted with effective microbes over two years. Similarly, the addition of effective microbes has increased the emergence m -2 (123), leaf area tiller -1 (105.6 cm 2 ), plant height (96.6 cm) and biomass (11386 kg ha -1 ). The physiological maturity delayed when FYM increased from 0 to 20 Mg ha -1 and applied with effective microbes. However, using >10 Mg FYM ha -1 has no differences in emergence m -2 across the amendments. In conclusion, the addition of effective microbes can enhance crop stand and biomass when added with 15-20 Mg FYM ha -1 .