生物炭不同施用量对烟草根际土壤真菌群落结构的影响

Effect of different application of biochar application on fungal community structure in tobacco rhizosphere soil

【目的】为探明生物炭施用量对烟草旺长期根际土壤真菌种群结构、多样性和生态功能的影响,以期为改善烟草根际土壤微生态环境以及为生物炭在植烟土壤中的应用提供参考。【方法】以烟草品种“红花大金元”为试验材料,在施肥减量10%的前提下,设置施用生物炭250 g/株(A1)、300 g/株(A2)和350 g/株(A3)3种处理,并以常规施肥为对照。采用Illumina MiSeq高通量测序技术对不同处理旺长期烟株根际土壤真菌ITS1基因进行测定。【结果】施用生物炭可以改变土壤真菌α多样性和种群结构,在所有土壤样品中A3处理真菌多样性及丰富度最高。门水平上,各处理主要优势菌门为子囊菌门(Ascomycota)和担子菌门(Basidiomycota),其中子囊菌门相对丰度与生物炭施用量呈负相关,担子菌门相对丰度与生物炭施用量呈正相关。纲水平上,施用生物炭降低了粪壳菌纲(Sordariomycetes)和散囊菌纲(Eurotiomycetes),提高了伞菌纲(Agaricomycetes)和银耳纲(Tremellomycetes)的相对丰度。属水平上,施用生物炭显著降低了青霉菌属(Penicillium)、枝孢瓶霉属(Cladophialophora)、螺旋聚孢霉属(Clonostachys)等真菌相对丰度;提高了镰刀菌属(Fusarium)、Saitozyma、锥盖伞属(Conocybe)、附球菌属(Epicoccum)等真菌相对丰度。FUNGuild真菌功能预测发现,各样本根际土壤真菌的功能类型以腐生营养型与腐生营养型—共生营养型为主。生物炭处理中植物病原相对丰度均低于对照。【结论】烟株施用生物炭350 g/株有效改善了根际土壤真菌群落结构,有利于维持土壤真菌的多样性和丰富度、降低土壤病原真菌的丰度,可为植烟区合理施用生物炭提供技术指导。

【Objective】The purpose of the paper is to explore the impact of biochar on the population structure,diversity and ecological function of fungi in long-term rhizosphere soil and provide insights for improving the microecological environment of tobacco rhizosphere soil and biochar application in tobacco planting soils.【Method】In the study,‘Honghuadajinyuan'tobacco was utilized as the test material.Under the premise of reducing the fertilizer amount by 10%,250 g/plant(A_1),300 g/plant(A_2)and 350 g/plant(A_3)of bio-carbon fertilizer were applied,with conventional fertilizer used as the control.Illumina MiSeq high-throughput sequencing technology was employed to determine the rhizosphere soil microorganisms of tobacco plants subjected to these different treatments.【Result】The application of biochar fertilizer had a significant impact on soilαdiversity and population structure,with A_3 treatment demonstrating the highest fungal diversity and abundance among all soil samples.At the phylum level,there was a negative correlation between the relative abundance of Ascomycota and the amount of biochar fertilizer applied,while the relative abundance of Basidiomycota exhibited a positive correlation with the quantity of biochar fertilizer application,both of which were the primary dominant bacteria fungi in each treatment.At the genus level,the application of biochar fertilizer led to a significant decrease in the relative abundance of Penicillium,Cladophialophora,and Clonostachys,while significantly increased the relative abundance of Fusarium,Saitozyma,Conocybe.Addtionally,using FUNGuild for fungal function prediction,it was observed that the functional types of rhizosphere soil fungi in each sample were primarily saprophytic and saprophytic-symbiotic.Furthermore,the relative abundance of plant pathogen in soil samples with biochar fertilizer was lower compared to the control group.【Conclusion】The study shows that the A_3 treatment improves the fungal community structure in the rhizosphere soil of tobacco plants,which is more conducive to maintaining the balance of soil ecosystem and restoring soil quality.It can provide technical reference for rational application of biochar fertilizer in tobacco planting areas.