Inoculant production and quality control

The manufacture of high-quality inoculants increases the potential for maximum nitrogen fixation in inoculated legumes (see Chapters 1, 5, 8 and 10). If legume inoculation is successful, the inoculant strain will colonise the rhizosphere and compete with resident soil rhizobia for nodulation sites on the host legume root. Researchers too must prepare high quality inoculants for experimental field trials, similar to those described in Chapter 8. Large-scale production of high-quality legume inoculants is complex. It requires expert skills in aseptic handling of rhizobia, an understanding of the conditions in which rhizobia grow and survive, research and development to find suitable carrier materials for inoculant formulation, and a program of quality control and quality assurance to maintain the manufacturing process and product integrity. There are several other publications describing methods involved in legume inoculant quality control; comprehensive texts have been published by Vincent (1970) and Somasegaran and Hoben (1994).