Integrated Use of Biofertilizers, Compost, and Mineral Fertilizers to Improve Wheat Productivity and Soil Fertility in Calcareous Soils

Wheat (Triticum aestivum L.) is an essential crop with considerable economic and nutritional significance. However, its productivity is often hindered in calcareous soils due to limited nutrient availability, low organic matter content, and high soil pH, all of which reduce nutrient uptake efficiency. This study examines the effect of arbuscular mycorrhizal fungi (AMF) and yeast inoculation, in conjunction with compost application, on wheat yield, nutrient content, and soil properties under calcareous soil conditions. A field experiment was conducted over two consecutive growing seasons at the El-Nubaria Agricultural Research Station in Egypt, utilizing a split-plot design. The main treatments consisted of three rates of compost (0, 15, and 30 m³ fed-1), while the sub-main treatments included varying levels of mineral fertilizers (100, 75, and 50% NPK) and biofertilizers (AMF, yeast, and combination of both). The results showed that the integration of compost with biofertilizers significantly enhanced plant height and grain yield. The highest grain yield recorded was 2.73 tons fed-1, with a biological yield of 11.76 ton fed-1, achieved through the application of 30 m³ fed-1 of compost combined with both AMF and yeast. Additionally, the nutrient content in wheat grains and straw, including nitrogen, phosphorus, and potassium, showed notable increases with biofertilizer treatments. Soil quality parameters, such as organic matter content, mineral nitrogen (135.33 ppm), available phosphorus (13.99 ppm), and exchangeable potassium (212.68 ppm), were significantly improved in plots treated with compost. Furthermore, microbial activity, indicated by soil respiration and mycorrhizal spore count, increased with the combined application of compost and biofertilizers. These findings illustrate the potential of utilizing compost in combination with microbial inoculants as a sustainable agricultural practice to enhance wheat productivity and improve soil fertility in calcareous soils.