Fig. 2. The effects of inoculated mutants/strains of Bradyrhizobium japonicum on soybean (cultivars Maple Glen and OAC Bayfield) plant leaf area during the 1998 and 1999 seasons. Each value is plotted as the mean + S.E. (n = 10). The plant development stage at each harvest was: 1. V3 (35 DAP in 1998 and 36 DAP in 1999); R1 (43 DAP in 1998 and 44 DAP in 1999); R4 (73 DAP in 1998 and 77 DAP in 1999) and R8 (90 DAP in 1998 and 91 DAP in 1999).