Work

Optimizing N-P-K ratios with magnesium supply improves tea yield and quality primarily by modulating soil bacterial communities in an albino tea plantation

Year: 2026

Type: article

Abstract: Anji Baicha is produced from 'Baiye 1', which is an albino cultivar of tea (Camellia sinensis). It is highly prized for its unique characteristic of accumulating high levels of free amino acids, especially theanine. Conventional fertilization practices used to maintain leaf albinism often compromise yield and quality. Therefore, the present study used an optimized fertilization strategy, combining adjusted N-P-K ratios with Mg supplementation, to enhance plant nutrition while preserving the desired albinism feature. Field experiments were carried out to compare farmers' practice (FFP), optimized N-P-K (OPT), and OPT+Mg. Compared with FFP, OPT, and OPT+Mg treatment significantly increased tea yield by 22%–29% and the amino acid (including theanine) content in new shoots (p > 0.05), while successfully maintaining leaf albinism. They also improved soil nutrient availability, microbial diversity, and enhanced soil quality by 19.4%–75%. Both OPT and OPT+Mg treatments reshaped soil bacterial and fungal communities, enriching specific beneficial microbial taxa. Random Forest predictive analysis indicated that bacterial biomarkers exerted a greater influence on tea yield and amino acid content than fungal biomarkers, accounting for 57% and 51.4% of the predicted variance for yield and amino acids, respectively (compared to 43% and 48.6% for fungi). Acidicaldus and Deniquelata were identified as key biomarkers for yield, while Cupriavidus and Aspergillus were key biomarkers associated with variation in amino acid content. Thus, findings demonstrate that adequate N fertilization is crucial for optimal growth of this albino tea cultivar, and Mg supplementation under optimal N supply provides synergistic advantages. The study establishes a scientific framework for the sustainable production of Anji Baicha.

Source: Beverage Plant Research

DOI: 10.48130/bpr-0025-0043