Work

Effects of water and fertilizer optimization on rhizosphere priming and regenerating capacity of perennial rice

Year: 2026

Type: article

Abstract: As the ratoon season progresses in perennial rice, strengthening rhizosphere regulation during late growth is important for improving the soil micro-ecological environment, preventing stubble-related continuous-cropping constraints, and sustaining high and stable yields in perennial systems. Here, we used Yunda 25 (YD25) and conducted a pot experiment with three water and fertilizer regimes applied at the ratoon tillering stage: flooded irrigation without seedling-boost fertilizer (S), alternate wetting and drying without seedling-boost fertilizer (G), and alternate wetting and drying with seedling-boost fertilizer (GF). We assessed the effects of these regimes on ratoon-season yield, rhizosphere soil enzyme activities, and microbial functional diversity.The water–fertilizer treatments significantly affected rhizosphere redox potential and soil enzyme activities. Compared with S, GF and G significantly increased polyphenol oxidase, peroxidase, urease, and sucrase by 36.17%–39.01%, 5.56%–18.23%, 30.92%–56.83%, and 38.11%–64.16%, respectively. Ratoon-season yield increased by 34.47%–36.69% under GF and by 19.51%–22.23% under G. Microbial functional diversity in carbon-source metabolism also differed significantly among treatments. Relative to S, GF and G increased substrate utilization of amino acids, polymers, amines, carboxylic acids, and carbohydrates by 34.40%–39.23%, 67.62%–69.92%, 63.10%–75.56%, 18.48%–42.71%, and 53.53%–66.72%, respectively.Chessboard scores and correlation analyses further indicated that water and fertilizer coupling promoted positive feedbacks in the rhizosphere micro-ecosystem and increased the relative abundance of beneficial functional genera, including Bacillus, Pseudomonas, Burkholderia, Streptomyces, and Nitrosospira. These changes improved soil micro-ecological conditions and enhanced nitrogen cycling, as indicated by higher expression and mineralization related to ammonia-oxidation genes amoA (AOA) and amoA (AOB), nitrate-reduction gene narG, and denitrification genes nirK, nirS, and nosZ. As a result, rhizosphere nutrient activation and effective nutrient supply increased, root vigor improved, and plants achieved faster early growth and higher yield. Overall, alternate wetting and drying combined with seedling-boost fertilizer (GF) showed the strongest regulating effect during the ratoon season.

Source: Plant Growth Regulation

DOI: 10.1007/s10725-026-01455-2