Cover crop cultivation and incorporation improve phosphorus fertilizer-use efficiency by subsequent wheat crop

Abstract Background and aims Efficient phosphorus (P) management is a major challenge in agriculture. Plants exhibit diverse P-mobilizing mechanisms, which can affect the P uptake by the subsequent crop. Information on this topic is scarce, and this study aimed to assess the effect of different cover crops (CC) on P uptake by the subsequent cash crop (durum wheat, Triticum durum L.) under different soil conditions and fertilization regimes. Methods A pot experiment was conducted under controlled conditions involving different CCs: Avena sativa (Av); Vicia sativa (Vs); Vicia narbonensis (Vn), Av + Vs. and Av + Vn. Two soils with low available P status and different properties dominating P dynamics were used: a carbonate-rich soil (S-Ca) and a Fe oxide-rich soil (S-Fe). After CC termination and residue incorporation, wheat was grown with and without P fertilization. Results Olsen P significantly decreased after CC termination but partially recovered after CC incorporation due to P turnover from decaying material and microbial activity, explaining why P uptake by unfertilized wheat did not decrease after CC. Depending on the soil, CCs increased the apparent P recovery (APR) from applied fertilizer by 2–6 times. Oat was the most effective in increasing APR in the S-Fe, and Vs and Av + Vn in the S-Ca soil. Physiological P use efficiency (PUtE) worsened with some CCs when P fertilizer was applied. Conclusion These results reveal that CCs contribute to greater efficiency in the use of applied P and enhance soil P cycling, thus contributing to more sustainable P management in agroecosystems.