不同施肥水平下甘蔗植株根系内生细菌群落结构特征

分析不同施肥水平下甘蔗植株根系内生细菌群落结构特征,旨在解析不同施肥水平对甘蔗植株内生细菌群落的影响,为挖掘和利用有益内生细菌及其功能提供理论依据。结果发现,门分类水平,施肥处理条件下甘蔗植株根系中放线菌门(Actinobacteria)细菌丰度占比均低于相应的不施肥处理,但绿弯菌门(Chloroflexi)细菌丰度占比均高于不施肥处理。属分类水平,Haliangium、 Acidicapsa、 unclassified＿f＿＿Ktedonobacteraceae和unclassified＿f＿＿Acidobacteriaceae＿Subgroup＿1是常规施肥水平(3000kghm^-2,H处理)条件下甘蔗植株根系特有的优势内生细菌属;而鞘氨醇单胞菌属(Sphingomonas)是减量施肥水平(1500 kg hm^-2, M处理)下特有的优势内生细菌属;中慢生根瘤菌属(Mesorhizobium)、 norank＿f＿＿BIrii41、糖霉菌属(Glycomyces)、 norank＿f＿＿67-14、 Reyranella、 unclass...

Characteristics of endophytic bacterial community structure in roots of sugar-cane under different fertilizer applications

To explore the beneficial endophytic bacteria in sugarcanes and their functions,we analyzed the characteristics of endophytic bacterial community structure in roots of sugarcane under different fertilizer applications.At the phylum level,the proportion of Actinobacteria in roots of sugarcanes under different fertilization levels were lower than that in the control.However,the proportion of Chloroflexi in roots of sugarcanes under different fertilization levels applications were higher than that in CK.At the genus level,Haliangium,Acidicapsa,unclassified_f__Ktedonobacteraceae,and unclassified_f__Acidobacteriaceae_Subgroup_1 were the specific dominant endophytic bacterial genera in root of sugarcanes under conventional fertilization level(3000 kg hm^-2,H treatment);while Sphingomonas was the specific dominant endophytic bacterial genus in roots of sugarcanes under fertilization level(1500 kg hm^-2,M treatment);Mesorhizobium,norank_f__BIrii41,Glycomyces,norank_f__67-14,Reyranella,unclassified_f__Steroidobacteraceae,unclassified_f__Xanthobacteraceae,norank_f__Roseiflexaceae,and Dongia were the specific dominant endophytic bacterial genus in roots of sugarcanes under the fertilization level(300 kg hm^-2,L treatment).On the contrary,Caulobacter,Pseudonocardia,Nocardia,Kitasatospora,norank_f__norank_o__norank_c__Actinobacteria,Oce-anibaculum,and Amycolatopsis were the unique dominant endophytic bacterial genera in root of sugarcane without fertilization application(control).And Actinospica,Catenulispora,Acidothermus,Dyella,and norank_f__Xanthobacteraceae were lost in root of sugarcanes under low nitrogen applications.Gene function prediction also revealed that,compared to no-fertilization treatment,both the endophytic bacterial community structure and the metabolic functions of endophytic bacteria in roots of sugarcanes were affected by different fertilizer applications.However,the structures of endophytic bacterial community in roots of sugarcane were significant differences among different fertilization treatments depending on the amounts of fertilizer applications.Compared to conventional fertilization,the yields of sugarcanes,and the structure,metabolic function of endophytic bacteria in roots of sugarcanes were not significantly changed by fertilizer application under 1500 kg hm^-2 treatment.In conclusion,the conventional fertilization at the present stage can be substituted by reducing fertilizer application from 3000 kg hm^-2 to 1500 kg hm^-2 level in sugarcane.