Fig. 2.

The relative abundance of each of four strains comprising the bradyrhizobial community structure in microcosms in an experiment examining combinations of two soil types (A: ADS and B: GLS), two soil moisture conditions (non-flooded, N, and flooded, F), and three temperature conditions (H: 30°C, M: 25°C, L: 20°C) after 0-, 30-, and 60-d incubations.

Each value is the mean±standard deviation of three replicate microcosms (n=3). A significance test was conducted between incubation periods per strain per microcosm (Bonferroni, p<0.05). The four strains of Bradyrhizobium were B. japonicum USDA6^T (U6), B. elkanii USDA76^T (U76), B. diazoefficiens USDA110^T (U110), and B. japonicum USDA123 (U123). In half of the WT set microcosms (W), U110 was the USDA110^T wild-type strain possessing the nosZ gene, and in the other half of the Mut set (D), U110 was the USDA110ΔnosZ mutant that lacks the nosZ gene. The other three strains remained the same in all incubations. Microcosm nomenclature follows the abbreviations above, such that ANW_H indicates a microcosm with andosol, non-flooding condition, WT set, incubated at high temperature.