Introducing unprocessed oil-tea waste leads to imbalance of microbiome and disease spread for near-natural cultivation of shorthairy antenoron.

The application of oil-tea waste, a byproduct derived from edible-oil tree (Camellia oleifera Abel) oil production, is frequently regarded as a sustainable approach for under-forest cultivation. Nevertheless, the ecological ramifications of utilizing unprocessed oil-tea waste remain inadequately elucidated. In this study, we aim to assess its impacts on the growth, health status, and fungal community composition of shorthairy antenoron (Anoectochilus roxburghii) under near-natural cultivation conditions. We integrated field experiments with ITS amplicon sequencing of bulk soil, rhizosphere soil and root endophytes to investigate the effects of unprocessed oil-tea waste on the growth and health of shorthairy antenoron, as well as the correlation between the effects and microbiomes. Our study demonstrated that unprocessed oil-tea waste markedly inhibited plant growth and exacerbated disease symptoms, particularly at elevated application rates. These detrimental effects correlated with the proliferation of pathogenic fungi (e.g., Fusarium, Ilyonectria) concomitant with a decline in beneficial taxa (e.g., Trichoderma, Umbelopsis), culminating in a disruption of the rhizosphere microbial equilibrium. Functional annotation further revealed a pronounced shift toward pathogen-dominated fungal communities. Correlation analyses substantiated significant negative relationships between pathogen abundance and plant performance metrics, whereas beneficial fungi exhibited positive correlations. Collectively, this study highlights the ecological risks associated with the application of unprocessed organic waste and provides microbiome-informed perspectives to guide the sustainable management of under-forest medicinal plant cultivation.