FIG 2.

Chlorophyll content and growth promotion of soybean inoculated with either USDA110 WT or the ΔssuD mutant strains. (A) Chlorophyll levels in the leaves of uninoculated or inoculated soybean plants. The plants inoculated with the ΔssuD mutant showed significantly less chlorophyll than those inoculated with the WT strain but more than the uninoculated plants. (B) Shoot dry weights of plants inoculated with the ΔssuD mutant were similar to those of the uninoculated plants and significantly less than the WT inoculated plants. The results are the means ± standard deviations (SDs) from three independent observations, with six plants each. Bars with different lowercase letters are significantly different (P < 0.05) from each other.