Exploring phosphorus fertiliser management in wheat production

Efficient utilisation of phosphorus (P) is paramount for crop production, resource sustainability, and food security. For responsible management of P fertilisers across varying fertilisers supply scenarios in wheat cultivation, it is imperative to systematically assess the impact of soil characteristics, crop varieties, and crop rotation practices on P efficiency. The yield response to applied P (YRP) and the agronomic efficiency of applied P (AEP) were investigated in 2872 field experiments across the major wheat production areas of China. The influence and relative importance of these factors under the different P treatments were quantified and identified. Across all farms, the average wheat yields in the CK (no P application), 100%P (locally recommended dosage), 50%P, and 150%P treatments were 5574, 6472, 6098, and 6384 kg ha−1, respectively. The highest YRP was obtained in the 100%P treatment (18.2%), while the AEP decreased from 20.7 kg kg−1 to 10.8 kg kg−1 as the P supply increased from 50%P to 150%P treatment. Both YRP and AEP were significantly influenced by soil organic matter (SOM) and available P (Olsen-P). In addition, varieties with better advantages in terms of YRP and AEP were identified in Regions I, II, and III. Random forest analysis showed that the importance of the variables for YRP and AEP differed substantially with different P treatments, suggesting that different strategies are required for different farmland management units. However, regardless of whether P fertilisers was insufficient or excessive, variety was the most important variable for enhancing P-use efficiency. In conclusion, this analysis is useful for the better management of P fertilisers in wheat production.