Screening and identification of a soil-derived strain Penicillium ludwigii X-16 and its organic and inorganic nitrogen utilization characteristics
Chemical nitrogen fertilizer retention in the soil,except for the nitrogen absorbed by crops,helps to improve the use efficiency of chemical nitrogen fertilizer,reduce the amount of chemical nitrogen fertilizer,and reduce environmental nitrogen pollution.In this study,inorganic nitrogen was used as the sole nitrogen source for the enrichment culture,and the inorganic nitrogen-immobilizing fungus strain X-16 was isolated and screened from acidic upland red soils.After morphological observations and ITS gene homology analysis,strain X-16 was identified as Penicillium ludwigii.After monitoring the growth of the strain in a liquid medium with different organic and inorganic nitrogen sources strain X-16 was observed to be able to use inorganic nitrogen,amino acid nitrogen,and complex organic nitrogen(zein protein)for growth,especially complex organic nitrogen.Among all strains,X-16 achieved the highest microbial biomass(1.93±0.50 g L-1),inorganic nitrogen immobilization rate(0.57±0.10 mg L-1 h-1),and organic nitrogen mineralization rate(0.57± 0.13 mg L-1 h-1)when treated with zein-protein.Compared to that of the uninoculated control,inoculation with X-16 significantly increased the soil immobilization rate of chemical nitrogen fertilizer by 492％.This translates to an increase of 0.78±0.06 mg kg-1 d-1.In this study,a dominant inorganic nitrogen immobilization fungal strain was screened from acidic upland red soils.This strain had solid inorganic nitrogen assimilation ability.It could mineralize complex organic nitrogen sources into ammonium,providing a theoretical basis and strain resources for inorganic nitrogen fixation of fertilizers and organic nitrogen release studies of soil sources.
NETL
NSTL
万方数据
