Phosphorus fertilisation and biochar impacts on soil fertility and wheat (

The Egyptian soil contains low organic matter and high calcium carbonate with a pH of 7.5–8.2, which reduces the availability of phosphorus (P) improve the efficiency of applying P fertilisers in alkaline soils. Therefore, the aim of this study is to evaluate the effect of biochar (B) at 0 t ha−1 and 10 t ha−1 with different P fertiliser rates (i.e. 0% P, 50% P, 100% P and 150% P of the recommended dose) on wheat yield (Triticum aestivum L.) and soil fertility in clay texture soil during the 2015–2016 and 2016–2017 growing seasons. The results show a significant increase in all of the following: soil availability and plant uptake of NPK; flag leaf area (FLA); the number of fertile tillers (NFT); the number of grains in spike (NGS), and the grain yield of wheat plants treated with P fertiliser alone, or when P fertiliser combined with biochar addition. FLA increased by 81.82% and 72.27% in the plots treated with biochar during the 1st and 2nd seasons respectively. Wheat uptake of total nitrogen–P–potassium (NPK) increased as a result of increasing the concentration of inorganic P in the studied soil. It is noteworthy that adding biochar to P fertiliser supplements P-fertiliser such as in the treatment of 10 t ha−1 biochar at 50% P, where the highest grain yield was recorded compared with adding 100% P and 150% P of the recommended dose. The results indicated that integrating biochar and P fertiliser can be a practical approach to improve wheat production and soil fertility.