Effects of tea gardens of different tree ages on soil microbial community structure and diversity in southern Henan

【Objective】 This paper explored the effects of tea gardens of different tree ages in Xinyang, southern Henan, on soil microbial community structure and diversity, to provide reference for improving soil management in tea gardens in southern Henan.【Method】 In the autumn of 2021, Illumina MiSeq high-throughput sequencing technology was used to study the soil fungal and bacterial community structure characteristics of 5 years old, 11 years old and 18 years old tea gardens in Xinyang. The effects of soil physical and chemical factors on soil fungal and bacterial community structure were analyzed.【Result】 The soil bacterial diversity of planted tea gardens with tea trees of 3 different age was higher than that of unplanted tea gardens soil. Except for 5 years old tea gardens without endemic bacterial OTU, the rest of the test soil had endemic bacterial OTU, and the 18 years old tea gardens had the most endemic bacterial OTU. Planting tea trees was beneficial to improving soil bacterial diversity and relative abundance within a certain planting years. The dominant species of bacteria and fungi changed after tea planting, among which the relative abundance of Acidobacteriia and Bacteroidia changed the most significantly. With the increase of planting years, Acidobacteriia basically showed a trend of increasing and then decreasing, while Bacteroidia showed a trend of decreasing and then increasing. The relative abundance of Eurotiomycetes and Agaricomycetes in the soil planted tea increased significantly while the relative abundance of Sordariomycetes declined, the trend of change being not obvious among the tea gardens of different ages. The relative abundance of Agaricomycetes and Leotiomycetes tended to increase with the increase of planting years. The three most abundant bacteria in tea garden soil were Acidobacteriia, Alphaproteobacteria and Verrucomicrobiae, while the three most abundant bacteria in unplanted tea garden soil were Bacteroidia, Alphaproteobacteria, and Clostridia, showing great difference. With the increase of planting years, the soil pH gradually decreased. Soil environmental factors excerted greater effect on bacteria than fungi, and soil pH was the most important soil environmental factor affecting bacteria and fungal communities structure and α diversity.【Conclusion】 The years of tea planting significantly change the soil pH and the contents of hydrolytic nitrogen, available phosphorus and available potassium, and also significantly change the structure and abundance of bacterial and fungal communities in the soil. With increase of tree age, the diversity and relative abundance of bacteria in the soil of tea garden change more greatly than that of fungi.