关键词: 鼠茅草, 茶, 间作, 土壤微生物, 品质成分

Abstract:

【Objective】 The objective of this study was to analyze the impact of intercropping Vulpia myuros on soil nutrient composition, soil microbial community structure, and tea quality components in tea plantations, so as to provide the data support for intercropping V. myuros as a means to enhance the ecological environment and quality of tea cultivation.【Method】The experimental materials consisted of soil and fresh leaves from a tea garden that had been intercropped with V. myuros for a duration of 2 years, and the control group was a clear-ploughed tea garden. The pH, organic matter, and mineral nutrients of the topsoil in the tea garden were measured. Additionally, the population structure of soil bacteria and fungi was analyzed using 16S and ITS high-throughput sequencing techniques. The quality components of tea were determined through Agilent-7890B gas chromatography.【Result】After intercropping V. myuros in a tea garden for 2 years, the soil pH increased by 0.29, and the soil organic matter content increased by 16.46 g∙kg^-1. Additionally, the available phosphorus, available potassium, ammonium nitrogen, and nitrate nitrogen also increased to varying degrees in the tea garden soil planted with V. myuros. Notably, the available phosphorus was 5.88 times higher in the intercropped tea garden compared with the clear-cultivated tea garden. The total nitrogen content in the V. myuros plantation soil was higher than that in the clear-cultivated tea plantation, while the total phosphorus, potassium, and sodium contents were lower. Moreover, the tea garden soil planted with V. myuros had higher levels of available zinc, available iron, available copper, and cation exchange capacity. The intercropping of V. myuros in the tea garden also led to an increase in the number of bacteria and fungi in the soil. Furthermore, the relative abundance of Actinobacteria and Ascomycota associated with organic matter decomposition increased in the soil of the V. myuros tea plantation. A total of 259 metabolites were identified from the fresh leaves of the grass plantation and the clear cultivation garden. Among them, the content of 20 metabolites showed significant differences, and these different metabolites mainly included sugars, fatty acids, and catechins. The tea leaves of the V. myuros plantation had more than 2 times the contents of leucrose, methyl-β-D-glucopyranoside, lacttol alcohol, galactoglycerol, and α-lactose compared to the tea plantation. On the other hand, the content of (9Z)-octadecatrienoic acid and (9Z,12Z,15Z)-octadecatrienoic acid were significantly lower in the cultivated tea garden. Additionally, compared with the clear-ploughed tea garden the intercultivated tea plantation had significantly lower contents of (+)-galligallocatechin, galligallocatechin, and epicatechin metabolites. 【Conclusion】When V. myuros was interplanted with tea gardens, the acidity of the soil might be successfully alleviated, and the amount of organic matter and mineral nutrient components in the soil increased. Then, tea plants could more easily absorb and use soil nutrients when there were changes in the amount and community structure of soil bacteria and fungi. The structure of the microbial population and variations in soil nutrients had a significant impact on the quality of tea.

Key words: Vulpia myuros, Camellia sinensis, intercropping, soil microorganisms, quality components