Fundamental molecular techniques for rhizobia

Study of the legume/rhizobium symbiosis necessitates an understanding of methods to isolate and characterise the bacteria. Since the publication of ‘A manual for the practical study of root-nodule bacteria’ by Jim Vincent (1970) a number of sequels have been published, such as the NifTAL, CIAT and CIMMYT manuals, which are now out of date and out of print. Discoveries of a much wider range of root-nodulating bacteria than previously known means that even simple isolation methods need revisiting to ensure unusual types of bacteria are not discarded. Drawing on the rich experience from earlier publications, this manual brings together state-of-the-art methods for the study of root-nodule bacteria, both in the free-living state and in symbiosis with legumes. In each chapter, we introduce the topic and provide guidance on how study of the symbiosis might best be tackled. We then provide a detailed description of protocols that need to be followed and highlight potential problems and pitfalls. Topics covered include acquiring, recognising, growing and storing rhizobia, experimenting with strains in the laboratory, glasshouse and field, and applying contemporary molecular and genetic methodologies to assist in the study of rhizobia. We include a chapter that describes the current taxonomy and physiological understanding of rhizobia, and another on the production of inoculants and quality control in the supply chain