长期定位不同施肥类型对烟田土壤NosZ细菌群落结构的影响

Effects of Long-term Different Fertilization Types on Bacterial Community Structure with NosZ Gene in Tobacco Field Soil

为探究不同施肥类型对植烟土壤NosZ基因群落结构和丰度的影响。通过田间定位试验,研究长期单一施用化肥(T1)、化肥+稻草回田(T2)和化肥+稻草回田+饼肥(T3)等3个处理对烟田土壤化学性质及烟株根际土壤细菌多样性的影响。结果表明:①稻草回田处理与再增加饼肥处理的烟田土壤中NosZ基因的细菌α多样性,均高于单施化肥处理;②变形菌门(Proteobacteria)和该菌门下物种是细菌群落组成中的相对丰度最高的菌群,其中以稻草回田并添加饼肥处理最高,与土壤无机氮呈极显著正相关,并且与土壤N_(2)O排放呈负相关;③在聚类分析中稻草回田并增施饼肥处理的影响较大;④植烟土壤微生物LEf Se进化分支图表现优势的细菌种群,单施化肥的烟田土壤主要表现的优势细菌种群是Enterobacterales和Catenulisporales,而稻草还田的烟田土壤主要表现的优势细菌种群是Micrococcales。综上所述,长期定位施肥条件下,化肥配施稻草回田并增加饼肥,能够提高烟田土壤的细菌群落结构和相对丰度,并影响烟田土壤的N_(2)O排放。

To analyze the impact of long-term fertilization on NosZ gene community structure and abundance in flue-cured tobacco field under long-term fertilization,long-term single application of chemical fertilizer(T1),chemical fertilizer+rice straw returning(T2)and chemical fertilizer+straw returning+cake fertilizer(T3)on soil inorganic nitrogen and bacterial diversity in flue-cured tobacco rhizosphere were studied through field positioning experiments.The results showed that the bacterial α-diversity a in tobacco soil treated with rice straw returning+cake fertilizer were higher than that treated with chemical fertilizer alone.The relative abundances of Proteobacteria and the subphyla of Proteobacteria in bacterial community were the highest.The LEf Se phylogenetic cladistics of tobacco planting soil showed that the dominant bacterial populations in the tobacco soil under the 3 treatments of chemical fertilizer alone,chemical fertilizer+straw returning and fertilizer+straw returning+cake fertilizer were mainly Enterobacterales and Catenulisporales.In conclusion,straw returning+cake fertilizer could improve bacterial community structure and abundance and affect the N_(2)O content in tobacco field under long-term fertilization.