Effects of different organic manures on the biochemical and microbial characteristics of albic paddy soil in a short-term experiment

PLoS One. 2015 Apr 16;10(4):e0124096. doi: 10.1371/journal.pone.0124096. eCollection 2015.

Abstract

This study aimed to evaluate the effects of chemical fertilizer (NPK), NPK with livestock manure (NPK+M), NPK with straw (NPK+S), and NPK with green manure (NPK+G) on soil enzyme activities and microbial characteristics of albic paddy soil, which is a typical soil with low productivity in China. The responses of extracellular enzyme activities and the microbial community diversity (determined by phospholipid fatty acid analysis [PLFA] and denaturing gradient gel electrophoresis [DGGE]) were measured. The results showed that NPK+M and NPK+S significantly increased rice yield, with NPK+M being approximately 24% greater than NPK. The NPK+M significantly increased soil organic carbon (SOC) and available phosphate (P) and enhanced phosphatase, β-cellobiosidase, L-leucine aminopeptidase and urease activities. The NPK+S significantly increased SOC and available potassium (K) and significantly enhanced N-acetyl-glucosamidase, β-xylosidase, urease, and phenol oxidase activities. The NPK+G significantly improved total nitrogen (N), ammonium N, available P, and N-acetyl-glucosamidase activity. The PLFA biomass was highest under NPK+S, followed by NPK+M and NPK+G treatments. Principal component analysis (PCA) of the PLFA indicated that soils with NPK+M and NPK+S contained higher proportions of unsaturated and cyclopropane fatty acids (biomarkers of fungi and gram-negative bacteria) and soil under NPK+G contained more straight chain saturated fatty acids (representing gram-positive bacteria). PCA of the DGGE patterns showed that organic amendments had a greater influence on fungal community. Cluster analysis of fungal DGGE patterns revealed that NPK+G was clearly separated. Meanwhile, the bacterial community of NPK+M treatment was the most distinct. RDA analysis revealed changes of microbial community composition mostly depended on β-xylosidase, β-cellobiosidase activities, total N and available K contents. The abundances of gram-negative bacterial and fungal PLFAs probably effective in improving fertility of low-yield albic paddy soil because of their significant influence on DGGE profile.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria
  • China
  • Fungi
  • Manure*
  • Oryza / growth & development
  • Soil / chemistry*
  • Soil Microbiology*

Substances

  • Manure
  • Soil

Grants and funding

This research was supported by the earmarked fund for China Agriculture Research System (CARS-01-31), the National Basic Research Program of China (2013CB127405), the National Natural Science Foundation of China (Grant no. 31471943), and the Special Fund for Agro-scientific Research in the Public Interest (201003016). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.