高碳基肥减氮施用对植烟土壤总碳、总氮和真菌群落结构的影响

Effects of High-Carbon Basal Fertilizer Combined with Nitrogen Reduction on Total Carbon,Total Nitrogen and Fungal Community Structure in Tobacco-Planting Soil

本研究采用田间试验法,以常规施肥(纯氮111 kg·hm^(-2))为对照(GCK),设置高碳基肥450 kg·hm^(-2)+减氮10%(G3)、高碳基肥750 kg·hm^(-2)+减氮20%(G5)和高碳基肥1050 kg·hm^(-2)+减氮30%(G7)共4个处理,研究其对植烟土壤总碳、总氮含量的影响,并采用ITS测序技术分析烟田土壤真菌群落结构及其与土壤总碳和总氮的关系。结果表明:(1)高碳基肥减氮施用处理G7提高植烟土壤总碳含量和碳氮比(移栽后60、90 d),降低土壤总氮含量(移栽后60、90 d)。(2)高碳基肥减氮施用处理G3显著提高土壤真菌丰富度(移栽后30、90 d)。(3)高碳基肥减氮施用改变了真菌的群落结构,在门水平上提高了接合菌门(Zygomycota)相对丰度(移栽后60 d),降低了子囊菌门(Ascomycota)相对丰度;在属水平上提高了木霉属(Trichoderma)相对丰度,降低了镰刀菌属(Fusarium)相对丰度(移栽后60 d)。(4)高碳基肥减氮施用通过影响土壤总碳、总氮含量和碳氮比改变其真菌多样性和群落结构。本试验条件下,每公顷施用高碳基肥1050 kg+纯氮77.7 kg(G7)对植烟土壤总碳、总氮、碳氮比以及真菌群落结构影响较大。

In order to study the effect of high-carbon basal fertilizer application on tobacco-growing soil,the field experiment was adopted,and four treatments were set including conventional fertilization of pure nitrogen 111 kg·hm^(-2)(GCK),high-carbon basal fertilizer 450 kg·hm^(-2)combined with nitrogen reduction 10%(G3),high-carbon basal fertilizer 750 kg·hm^(-2)combined with nitrogen reduction 20%(G5)and high-carbon basal fertilizer 1050 kg·hm^(-2)combined with nitrogen reduction 30%(G7).The contents of soil total nitrogen(TN)and total carbon(TC)were determined,and soil fungal community structure and their relationships with TN and TC were analyzed by ITS sequencing technology.The results were as follows.(1)G7 treatment increased soil TC content and C/N ratio and decreased soil TN content at 60 and 90 days after transplanting.(2)G3 treatment significantly increased soil fungal diversity at 30 and 90 days after transplanting.(3)The application of high-carbon basal fertilizer combined with nitrogen reduction affected the community structure of fungi.In the phylum level,it increased the relative abundance of Zygomycota at 60 days after transplanting and decreased that of Ascomycota.In the genus level,it increased the relative abundance of Trichoderma and decreased that of Fusarium at 60 days after transplanting.(4)The application of high-carbon basal fertilizer combined with nitrogen reduction changed the fungal community structure through influencing soil TC,TN contents and C/N ratio.In conclusion,the application of 1050 kg of high-carbon basal fertilizer+77.7 kg of pure nitrogen per hectare(G7)had positive effects on soil fungal community structure and soil TC,TN and C/N ratio.