The current study evaluates the feasibility of amending a sandy soil with three different types of biogas manure (cattle dung alone BMC, cattle dung + jaw’s mallow wastes BMJ and cattle dung + mango wastes BMM) and their extractions (potassium humate HK, humic acid HA and fulvic acid FA) at two different rates (2 and 4%) to increase NPK uptake by faba bean plants and enhance their growth. To attain this aim, a pot experiment was conducted for 60 days during the winter season of 2019 following a randomized complete block design (RCBD). A control treatment, that received the recommended dose of NPK mineral fertilizers, was also considered for data comparison. Results reveal that the BMC biogas manure recorded the highest increases in faba bean dry weights (6.40g/pot) comparing with the results of other biogas manures. Generally, biogas manures seemed to be more efficient than their extracts on improving NPK uptake by plants and hence increase plant dry weights. Moreover, increasing the rate of application from 2 to 4% recorded further significant increases in this concern. On the contrary, BMM biogas manure was the least efficient organic treatment that increased faba bean growth when applied at a rate of 2% (4.72 g/pot). Thus, it can be deduced that different biogas manures enhanced the uptake of N P K by plants and increased their growth vs the control, especially when applied at a rate of 4%; yet the behavior of the organic amendments in soil varied considerably among the source of the organic amendment. |