Azospirillum– plant relationships: environmental and physiological advances (1990–1996)

This review presents a critical and comprehensive analysis of the developments in environmental and physiological studies related to Azospirillum interactions with plants based on information published between 1990 and 1996. It was designed as an update of a previous review with a similar scope. Apart from an update, this review emphasizes the central issues of Azospirillum research today, such as coinoculation with other microorganisms and hormonal studies, shows the less researched areas, and proposes possible avenues for the exploitation of this bacterium in areas other than agriculture.Key words: Azospirillum, bacterial inoculation, plant–bacteria interaction, plant growth promoting rhizobacteria, rhizosphere bacteria.