1999/12/01 by H. H. Zahran · 1,625 citations
Agricultural and Biological Sciences · #Agronomic Practices and Intercropping Systems #Agronomy #Arid #Bacteria #Biology #Ecology #Legume #Legume Nitrogen Fixing Symbiosis #Microbial inoculant #Nitrogen fixation #Rhizobia #Rhizobium #Soil Carbon and Nitrogen Dynamics #Soil fertility #Soil water #Symbiosis
paper · pdf · doi:10.1128/mmbr.63.4.968-989.1999
published in Microbiology and Molecular Biology Reviews 63(4), 968-989 (American Society for Microbiology)
openalex publication_date 1999/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Biological N(2) fixation represents the major source of N input in agricultural soils including those in arid regions. The major N(2)-fixing systems are the symbiotic systems, which can play a significant role in improving the fertility and productivity of low-N soils. The Rhizobium-legume symbioses have received most attention and have been examined extensively. The behavior of some N(2)-fixing systems under severe environmental conditions such as salt stress, drought stress, acidity, alkalinity, nutrient deficiency, fertilizers, heavy metals, and pesticides is reviewed. These major stress factors suppress the growth and symbiotic characteristics of most rhizobia; however, several strains, distributed among various species of rhizobia, are tolerant to stress effects. Some strains of rhizobia form effective (N(2)-fixing) symbioses with their host legumes under salt, heat, and acid stresses, and can sometimes do so under the effect of heavy metals. Reclamation and improvement of the fertility of arid lands by application of organic (manure and sewage sludge) and inorganic (synthetic) fertilizers are expensive and can be a source of pollution. The Rhizobium-legume (herb or tree) symbiosis is suggested to be the ideal solution to the improvement of soil fertility and the rehabilitation of arid lands and is an important direction for future research.