紫苏对医院绿地土真菌群落组成及生态功能群结构的影响

医院绿地土壤是医院人体病原真菌或潜在人体病原真菌重要的物种储存库。这些携带真菌孢子的土粒和灰尘在空气中的传播增加了医院院内真菌感染的风险,已成为一个日趋严重的公共卫生问题。现研究表明,不少高等植物,尤其是药用植物具很强的抗真菌特性。基于高通量测序及模拟盆栽试验,本研究观察了种植药用植物紫苏Perilla frutescens对医院绿地土壤真菌群落组成及生态功能群结构的影响。研究结果表明,医院绿地土壤真菌群落优势类群随紫苏生育期变化而发生明显变化。优势属由原初医院土（PTS）的绿僵菌属Metarhizium（60.94%）,依次变为紫苏生长期样本（GZS）的被孢霉属Mortierella（21.34%）、开花期样本（FZS）的亚隔孢壳科Didymellaceae中一未定属（47.22%）和枯萎期样本（WZS）的粪壳菌目Sordariales中一未定属（12.67%）。经FUNGuild平台对序列数据集作进一步解析发现,种植紫苏后能够驱动医院绿地土壤真菌生态功能群发生明显变化,一些分类单元由动物病原向腐生型和/或共生型生态功能群转变。动物病原菌群（包括人体潜在病原）相对丰度,由原初医院土（PTS）的61.36%,下调至紫苏生长期样本（GZS）的2.48%、开花期样本（FZS）的1.40%和枯萎期样本（WZS）的6.09%。研究揭示紫苏对医院绿地土壤真菌群落组成及相对丰度具有一定调控作用,尤其是可降低其中人体潜在病原相对丰度以减轻对人类健康的威胁,为引种药用植物增强医院绿地土壤健康水平及维护医院院内公共卫生安全提供了参考。

Effects of Perilla frutescens on the fungal community composition and ecological guild structure in a hospital grassplot soil

The soil of hospital grassplot is an important species repository of human pathogenic fungi or potential human pathogenic fungi. Airborne transmission of these soil particles and dust that carrying fungal spores increases the risk of nosocomial fungal infections, which has become an increasingly serious public health problem. Studies has shown that many higher plants, especially medicinal plants, have strong antifungal properties. Through the high-throughput sequencing technique and simulated pot experiments, the effects of Perilla frutescens on the fungal community composition and ecological guild structure in specific soil were studied and analyzed. The results indicated that dominant groups of fungal community significantly changed with the change of P. frutescens growth period. The dominant genus varied from Metarhizium (60.94%) in original hospital soil (PTS) to Mortierella (21.34%) in the soil of growing period (GZS), an unclassified genus in Didymellaceae (47.22%) in soil of flowering period (FZS) and an unclassified genus in Sordariales (12.67%) in soil of withering period (WZS). The sequence data sets were further analyzed by the FUNGuild platform. It was found that planting P. frutescens could change fungal ecological guilds in the soil significantly. Some fungal taxa varied their ecological function from animal pathogen to saprotroph and/or symbiotroph. The relative abundance of animal pathogen (including potential human pathogens) decreased from 61.36% in the original soil (PTS) to 2.48% in soil of vegetative growing period (GZS), 1.40% in soil of flowering period (FZS) and 6.09% in soil of wilting period (WZS) of P. frutescens. Results indicated that planting P. frutescens could regulate the composition and relative abundance of fungal community in the soil to a certain extent, especially reduce human potential pathogens, alleviating the threat of pathogens to human health. Introduction of medicinal plants into hospital grassplot soil seems advantageous to maintain the nosocomial public health safety.