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The aim of the present study was to investigate the possibility of replacing phosphorus chemical fertilizer (triple superphosphate) with biofertilizers as an environmentally friendly approach.  In this study, Possibility of replacing Triple superphosphate fertilizer with phosphate solubilizing bacteria "Pseudomonas deceptionensis Persian10 strain" in 10 treatments with two bacterial factors (in two levels of inoculation and non-inoculation) and chemical fertilizer (in five levels 0, 25, 50, 75 and 100% of the recommended amount of fertilizer in the pond) was examined in aquarium conditions. Treatments included: 1: 100% fertilizer + bacteria, 2: bacteria, 3: 25% fertilizer + bacteria, 4: 50% fertilizer + bacteria, 5: 75% fertilizer + bacteria, 6: 100% fertilizer, 7: 75% fertilizer, 8: 50% fertilizer, 9: 25% fertilizer, 10: control (without fertilizer and bacteria). Bacterial densities, soluble phosphorus, phosphatase and pH were measured on days 0, 2, 7, 12 and 17. The results showed that the phosphorus of all treatments had an increasing trend on different days and at the same time, an increase in the pH value and a decreasing trend was observed in the bacterial population and the amount of phosphatase enzyme. The highest amount of soluble phosphorus was observed in treatments 4 and 5. According to the obtained results, the application of 50% phosphate fertilizer + phosphate solubilizing bacteria can be recommended as a suitable ratio for the fertility of fish ponds and reducing the use of chemical fertilizers.

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Agriculture has always been a risky activity, and the first step in developing plans to face and overcome the risk is gleaning insight into the different types of risks and the risk factors. One of the risks faced in today’s agriculture sector is the production risk incurred by the inputs. The overarching goal of this research was to study the wheat production risk in Gorgan County, Iran, using the method proposed by using J-P (Just and Pope) approach. Data and information required for this research were obtained through stratified random sampling from 80 questionnaires completed in the 2015-2016 crop year. The estimation results suggested that with an increase in labor and farmers’ age, the production risk diminished, whereas the production risk escalated with an increase in the use of chemical fertilizers. Therefore, it is recommended to modify the usage pattern of this input to set the scene for the mitigation of the production risk of this crop in the region.

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The negative impact of excessive fertilization on the sustainable development of agriculture has become the focus of universal attention. Thus, the aim is to maximize the yield of rice without imposing too much damage on the environment. This paper uses data regression analysis based on the statistical data (from 1990 to 2020) of a certain region to explore the impact of fertilizer application on rice yield, and adopts the sensitivity analysis to study the sensitivity of rice yield to the applied amount of chemical fertilizer. The results show that the average rice yield increased with increasing Nitrogen (N) and potassium (K) fertilizers application within the statistical data range; while the average rice yield decreased as Phosphorus (P) fertilizer application increased. Simultaneously, increasing the application of N and K fertilizers improved the average rice yield. Reducing the amount of P fertilizer and increasing the proportion of K fertilizer positively affected the average rice yield. The sensitivity analysis indicated that the average rice yield was most sensitive to K application amount. The sensitivity value maximized at a small amount of N fertilizer (11.25 kg hm^-2) and a large amount of P fertilizer (6 kg hm^-2). The findings reveal the interactive effect of multiple fertilizer application rates on grain yield and address the unclear mechanism of single fertilizer application on grain yield in the existing research. This paper provides a theoretical basis for scientific fertilizer use, agricultural quality, efficiency improvement, and sustainable development of agriculture.