Pruning outweighs fertilization in shaping spring tea quality and yield through affecting soil microbiota during agronomic management

Abstract

Pruning and fertilization are prevalent agronomic practices in tea plantations, exerting regulatory effects on tea yield and quality. Considering the inherent complexity of the woody perennial system, the mechanisms governing the dynamic responses of tea plant under the combined application of pruning and fertilization remain largely obscure. To address this, we investigated the impacts of four agronomic treatments (light or heavy pruning in combination with pure chemical fertilizer or 25 % organic fertilizer substitution) on tea plant. Our findings demonstrated that modifications in pruning modes led to more notable increases in bud density and 100-bud weight of spring tea than fertilization changes. Furthermore, the principal quality components of spring tea were clustered into two groups based on pruning modes. Utilizing amplicon sequencing, we detected soil bacterial and fungal communities under four treatments, identified pruning-related bacteria and fungi. Redundancy analysis revealed that total phosphorus (TP) and total potassium (TK) were the dominant environmental factors shaping the soil microbial communities. Additionally, a strong correlation was found between soil fungi and metabolites, such as amino acids and catechins. Overall, our findings suggested that pruning exerts a more profound influence on tea yield and quality than fertilization by regulating metabolic pathways and reshaping the structures of soil bacterial and fungal communities. This study provides a theoretical foundation for elucidating how pruning and fertilization affect tea yield and quality, offers a reliable reference for optimizing tea plantation management strategies.