土壤性质对真菌温度敏感性的影响

Effects of soil properties on fungi temperature sensitivity

通过伽马灭菌的方式,将两种不同性质的土壤(自然土和农田土)进行灭菌,再互相接种未灭菌土壤,研究了改变土壤性质对真菌温度敏感性的影响。结果表明,改变土壤性质虽显著影响真菌总丰度,但对真菌总丰度的温度敏感性无显著性影响。然而,部分土壤真菌个体(分类操作单元OTU)对温度具有敏感性,改变土壤性质会对温度敏感真菌个体产生影响。首先,改变土壤性质使自然土壤真菌中的热响应真菌目的个数由2减少为1,使农田土壤真菌中的冷响应真菌目的个数由5增加到9;其次,升温使自然土壤的真菌在自然土壤中冷响应和热响应真菌累积相对丰度之和从2.22%减少为1.35%,在农田土壤中从1.25%减少为0.56%;升温使农田土壤的真菌在农田土壤中冷响应和热响应真菌累积相对丰度之和从13.66%增加到19.03%,在自然土壤中从6.01%减少为2.51%;再次,改变土壤性质使自然土壤的热响应真菌由Capnodiales、Chaetothyriales变为Eurotiales,农田土壤的热响应真菌由Capnodiales、Sordariales变为Chaetothyriales、Hypocreales;自然土壤的冷响应真菌由Chaetosphaeriales、Sordariales等变为Capnodiales、Hypocreales等,农田土壤的冷响应真菌由Chaetothyriales、Eurotiales等变为Capnodiales、Sordariales等;最后,各真菌在目水平上的相对丰度变化率也各不相同。本研究表明,改变土壤性质可显著影响真菌群落结构的温度敏感性,进而可能改变真菌功能的温度敏感性。

Effects of soil properties on fungi temperature sensitivity were studied with reciprocally transplanting two different unsterilized soils（ nature soil and farm soil） to gamma-sterilized soils. The results showed that soil properties significantly changed fungal total abundance,but didn＇t change the response of fungal abundance to temperature variation. However,some subgroups of the fungal community were sensitive to temperature change. Firstly,changing soil characteristic decreased the order number of warm-responsive fungi from 2 to 1 in nature soil fungi,and increased the order number of cold-responsive fungi from 5 to 9 in farm soil fungi; Secondly,increasing temperature changed relative abundance of cold and warm-responsive fungi of nature soil from 2. 22% to 1. 35% in nature soil,and from 1. 25% to 0. 56% in farm soil; changed relative abundance of cold and warm-responsive fungi of farm soil from 13. 66% to 19. 03% in farm soil,from 6. 01% to 2. 51% in nature soil;Thirdly,changing soil characteristic changed the warm-responsive fungi from Capnodiales, Chaetothyriales to Eurotiales in nature soil fungi,and from Capnodiales,Sordariales to Chaetothyriales,Hypocreales in farm soil fungi; changed the cold-responsive fungi from Chaetosphaeriales,Sordariales etc to Capnodiales,Hypocreales etc in nature soil fungi,and from Chaetothyriales,Eurotiales etc to Capnodiales,Sordariales etc in farm soil fungi. Finally,changing ratios of relative abundance were different among the fungal orders. This study showed that changing soil properties significantly affected temperature sensitivity of fungi community composition,which might change temperature sensitivity of fungal functions.