Implications of arsenic exposure for the soybean-Bradyrhizobium symbiosis
Little is known about the effects of As exposure on the legume-rhizobium symbiosis, and thus, on the potential for N-fixation in As contaminated ecosystems. A solution culture experiment was conducted to test the effects of As on the Clycine max (soybean)-Bradyrhizobium japonicum symbiosis. Increasing As in the solution increased the time to production of the first nodule (P<0.01) and decreased the number of nodules per plant (P=0.007), probably due to a decrease in root hairs reducing infection sites for B. japonicum. However, biomass was greater in inoculated, compared to uninoculated, plants even at high As concentrations, where nodulation was minimal (P<0.05) and tissue N (P=0.082) and As (P> 0.100) concentrations were not significantly affected by inoculation status. It is suggested that future research investigate the potential of free-living B. japonicum to mitigate the negative effects of excess As on the biomass production of plants.
arsenic Bradyrhizobium japonicurn legume, nitrogen fixation Glycine max (soybean)
S. M. Reichman
Soil and Physical Sciences Group, PO Box 84, Lincoln University, Lincoln, 7647, New Zealand
国际会议
第九届痕量元素生物地球化学国际会议(9th International Conference on the Biogeochemistry of Trace Elements)
北京
英文
712-713
2007-07-15（万方平台首次上网日期，不代表论文的发表时间）