Effect of N-fertilization, plant genotype and environmental conditions on nifH gene pools in roots of rice
Article first published online: 14 AUG 2003
Volume 5, Issue 10, pages 1009–1015, October 2003
How to Cite
Tan, Z., Hurek, T. and Reinhold-Hurek, B. (2003), Effect of N-fertilization, plant genotype and environmental conditions on nifH gene pools in roots of rice. Environmental Microbiology, 5: 1009–1015. doi: 10.1046/j.1462-2920.2003.00491.x
- Issue published online: 14 AUG 2003
- Article first published online: 14 AUG 2003
- Received 4 March, 2003; accepted 5 June, 2003.
Terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR-amplified nitrogenase gene (nifH) fragments is a rapid technique for profiling of diazotrophic microbial communities without the necessity of cultures for study. Here, we examined the impact of N-fertilization, plant genotype and environmental conditions on diazotrophic microbial populations in association with roots of rice (Oryza species) by T-RFLP community profiling and found marked effects on the composition of the microbial community. We found a rapid change of the diazotrophic population structure within 15 days after application of nitrogen fertilizer and a strong effect of environmental conditions and plant genotype. Control experiments revealed that phylogenetically distantly related nifH genes were proportionately amplified, and that signal strength reflected the relative abundance of nifH genes in the sample within a 10-fold range of template concentrations. These results clearly demonstrated that our T-RFLP method was suitable to reflect compositional differences in the diazotrophic community in a semiquantitative manner and that the diazotrophic rhizosphere communities of rice are not static but presumably rather highly dynamic.