Project R-5039

Basis for remediation of sites contaminated with potentially toxic elements in Zimapan (Hidalgo, Mexico): an interdisciplinary approach (Research)

Much of the research on endophytic bacteria has been focused at roots and stems. Little has done on seeds, regarding the composition and transfer of bacteria in contaminated environment. It is proposed to study seed endophytic bacteria of Crotalaria pumila growing naturally on mine tailings in a Mexican semiarid region. The plant accumulates Zn, Cd, Pb and Cu in shoots at concentrations higher than those phytotoxic for other species. Among 12 species found on mine tailings in 2011, C. pumila was the most abundant and the only one that completed their life cycle. In 2012, it was observed again but covering a larger area. Plants produced seeds too. The persistence of C. pumila could be attributed to the presence of benefical endophytic bacteria transferred from one generation to another trough the seeds. Thus, the aims are: to characterize genotypically and functionally the seed endophytic bacteria of C. pumila in three generations growing naturally on mine tailings; to compare these bacteria to those isolated from non-contaminated sites; to select bacteria useful to increase plant biomass production and tolerance to potentially toxic elements. The methodology is based on that probed previously by the Environmental Biology group at Hasselt University for artificial contaminated exposed seeds. The results obtained from this research will contribute to the understood of seed endophytic bacteria biology; as well as their possible uses in field.

01 January 2014 - 31 December 2017