Enhancing Pearl oyster mushroom (Pleurotus ostreatus (Jacq.) P. Kumm) performance by evaluating the influence of potassium humate and wheat straw on yield and biochemical attributes

This study investigated the effects of various combinations of potassium humate and raw wheat straw (RWS) treatments on the growth, yield, and quality of Pleurotus ostreatus (Jacq.) P. Kumm across two growing seasons. A total of seven treatment combinations (H0_RWS, H0.25_RWS, H0.5_RWS, H0.75_RWS, H1_RWS, H1.25_RWS, and H1.5_RWS) were applied to evaluate eleven traits, including soluble sugar content (SSC), fruiting body yield (FBY), biological efficiency (BE), and biochemical attributes. The analysis of variance revealed significant effects of both season and treatment on all traits, with notable interactions. The H0.5_RWS treatment demonstrated the highest improvements, increasing SSC by 15.3%, FBY by 18.6%, and vitamin C (VC) by 12.4% compared to the control. Utilizing principal component analysis (PCA) showed that the first two components explained 89.5% of the variance, with strong associations between SSC, VC, FBY, total phenolic content (TPC), BE, and peroxidase activity (POD) on PC1. The H0.5_RWS treatment was identified as the most effective for enhancing these parameters. Heatmap and radar plot analyses further confirmed the positive influence of moderate potassium humate doses, while higher doses resulted in reduced benefits. Correlation analysis showed strong positive relationships between yield and both total sugars (R² = 0.99) and BE (R² = 0.97). The results emphasize the substantial importance of balanced potassium humate application in enhancing the production and nutritional quality of P. ostreatus, providing valuable insights to optimize the cultivation practices of this species.