Occurrence of free-living nitrogen-fixing bacteria in soils of Trinidad and Tobago

Authors

  • Pamela Collins Department of Soil Science, Faculty of Agriculture, University of the West Indies, St Augustine, Trinidad
  • Alfred L. Donawa Department of Soil Science, Faculty of Agriculture, University of the West Indies, St Augustine, Trinidad

Keywords:

Soils, Nitrogen-fixing bacteria, Trinidad and Tobago

Abstract

Seventy-four (74) bacterial isolates from various soils and vegetation types in Trinidad and Tobago were identified as nitrogen fixers. Morphological and physiological characteristics indicated that the isolates belonged mainly to the genera Azotobacter, Clostridium, Bacillus and Beijerinkia. Others that could not be more clearly identified appeared to be of the Bacillaceae and Enterobacteriaceae families. None of the isolates were identified as Spirillum species although there was presumptive evidence of their presence. There were more isolates and greater physiological diversity among the isolates from rhizosphere compared with nonrhizosphere soils.

Issue

Section

Research Papers