Open AccessThe effects of stubble retention and nitrogen application on soil microbial community structure and functional gene abundance under irrigated maize
Author(s) -
Wakelin Steven A.,
Colloff Matt J.,
Harvey Paul R.,
Marschner Petra,
Gregg Adrienne L.,
Rogers Stephen L.
Publication year - 2007
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2006.00235.x
Subject(s) - biology , microbial population biology , community structure , agronomy , abundance (ecology) , denitrification , temperature gradient gel electrophoresis , nitrogen cycle , relative species abundance , fertilizer , nitrogen fixation , microbial ecology , nitrogen , ecology , bacteria , 16s ribosomal rna , genetics , physics , quantum mechanics
The effects of agronomic management practices on the soil microbial community were investigated in a maize production system in New South Wales, Australia. The site has been intensively studied to measure the impact of stubble management and N‐fertilizer application on greenhouse gas emissions (CO 2 and N 2 O), N‐cycling, pathology, soil structure and yield. As all of these endpoints can be regulated by microbial processes, the microbiology of the system was examined. Soil samples were taken after a winter fallow period and the diversity of the bacterial and fungal communities was measured using PCR‐denaturing gradient gel electrophoresis. Stubble and N shifted the structure of bacterial and fungal communities with the primary driver being stubble addition on the fungal community structure ( P <0.05 for all effects). Changes in C, N (total and NO 3 ), K and Na, were correlated ( P <0.05) with variation in the microbial community structure. Quantitative PCR showed that nif H (nitrogen fixation) and nap A (denitrification) gene abundance increased upon stubble retention, whereas amo A gene numbers were increased by N addition. These results showed that the management of both stubble and N have significant and long‐term impacts on the size and structure of the soil microbial community at phylogenetic and functional levels.