Rhizobium species involved in root nodule formation on legume plants are one of the best known groups of micro- organisms. The Rhizobium legume symbiosis continues to be of strategic importance particularly in the context of food production. As the world population grows, it is also neces- sary to have new developments taking place in crop improve- ment. The development and application of new technologies in biological sciences over the past number of years have made the entire area of plant-microbial interaction an exciting and challenging research area to be involved in. In view of the...