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Effective management of nitrogen (N), phosphorus (P), and potassium (K) are crucial for increasing crop production and productivity as they are associated with a number of enzymatic and physiological activities in wheat (Triticum aestivum L.). Field experiments were carried out during the winters of 2019˗˗20 and 2020˗˗21 to study the influence of varying levels of N, P, and K on crop performance, nutrient concentration, and uptake at various growth stages of wheat in mid-hill of Nepal. The study was conducted with factorial combinations of three N levels (100, 125, and 150 kg N ha−1), three P levels (25, 50, and 75 kg P2O5 ha−1) and three K levels (25, 50, and 75 kg K2O ha−1) in a randomized complete block design with three replications. Increasing N and K rates significantly (p <.05) increased total dry matter, grain yield, nutrient concentrations and uptakes in wheat. Pooled means showed significantly higher grain yields of 6.3 t ha−1 were obtained with N @ 125 kg ha−1, and K2O @ 50 kg ha−1 than lower rates. At maturity, average concentrations of N, P, and K in grain were 15.5, 3.6, and 5.8 g kg−1, respectively, and 5.4, 0.9, and 10.9 g kg−1 in straw, respectively, depending on the rate of NPK applied. N and P were mostly accumulated in wheat grain, whereas K was found higher in wheat straw than in grain. The nutrient concentration values of grain and straw can be used as a reference for determining nutrient removal from soil using a yield-based technique in wheat. [ABSTRACT FROM AUTHOR]

Field experiments were conducted to investigate the effect of various levels of nitrogen, phosphorus, and potassium on the nutrient content of maize grain and stover and their uptake at different growth stages of hybrid maize in silty clay loam soil of Khumaltar, Lalitpur, Nepal, during summer of 2019 and 2020. Experiment was carried out in three factorial randomized complete block design with a total of 27 treatment combinations and replicated 3 times. Three factors were three levels of nitrogen (150, 180, and 210 N kg/ha), phosphorus (40, 60, and 80 P2O5 kg/ha), and potassium (40, 60, and 80 K2O kg/ha). Increasing nitrogen and potassium rates significantly (p <.05) increased total dry matter, grain yield, nutrient concentration, and accumulation of NPK in maize. On average, application of a higher rate of nitrogen (210 kg/ha) and potassium (80 kg/ha) produced grain yields of 10.95 t/ha and 10.54 t/ha, respectively, indicating higher uptake and higher grain yield. The average concentrations of N, P2O5, and K2O were 15.79, 9.56, and 3.77 g/kg in grain and 6.74, 4.17, and 10.46 g/kg in stover at maturity differentiated depending upon the rate of NPK applied. Nitrogen and phosphorus were accumulated mostly in grain (68–83%), whereas potassium was observed more in stover (64–77%). On average, 9.97 tons of maize grain removed 282.81 kg NPK/ha with a positive linear regression (R2) value of 0.89. The reference value of nutrient contents in maize crop obtained from this study can be used to estimate the time and amount of NPK removed from soil for better nutrient management. [ABSTRACT FROM AUTHOR]

Abstract Background Building appropriate levels of trust in pharmaceuticals is a painstaking and challenging task, involving participants from different spheres of life, including producers, distributors, retailers, prescribers, patients and the mass media. Increasingly, however, trust is not just a national matter, but involves cross-border flows of knowledge, threats and promises. Methods Data for this paper comes from the project 'Tracing Pharmaceuticals in South Asia', which used ethnographic fieldwork and qualitative interviews to compared the trajectories of three pharmaceuticals (Rifampicin, Oxytocin and Fluoxetine) from producer to patient in three sites (north India, West Bengal and Nepal) between 2005-08. Results We argue that issues of trust are crucial in reducing the likelihood of appropriate use of medicines. Unlike earlier discussions of trust, we suggest that trust contexts beyond the patient-practitioner relationship are important. We illustrate these arguments through three case studies: (i) a conflict over ethics in Nepal, involving a suggested revised ethical code for retailers, medical representatives, producers and prescribers; (ii) disputes over counterfeit, fake, substandard and spurious medicines, and quality standards in Indian generic companies, looking particularly at the role played by the US FDA; and (iii) the implications of lack of trust in the DOTS programmes in India and Nepal for the relationships among patients, government and the private sector. Conclusions We conclude that the building of trust is a necessary but always vulnerable and contingent process. While it might be desirable to outline steps that can be taken to build trust, the range of conflicting interests in the pharmaceutical field make feasible solutions hard to implement.