MINERALOGY OF RHIZOSPHERIC AND NON-RHIZOSPHERIC SOILS IN CORN FIELDS

Technical limitations have restricted investigations of rhizosphere mi neralogy. Various analytical techniques were applied to assess root-mi neral associations and dynamics in natural soils under corn production . Soil samples were collected between four and five weeks after planti ng and included rhizospheric and non-rhizospheric soils, and undisturb ed block samples containing corn root systems. Analytical techniques w ere applied and included; X-ray diffraction, optical microscope, SEM, EDXRA with SEM, transmission electron microscope (TEM), electron energ y loss spectra with TEM, high-resolution transmission electron microsc ope (HRTEM) and microanalysis with HRTEM. The mineralogy of the rhizos phere differed from that of the bulk soil. Within the rhizosphere, min ute platy particles which were mostly vermiculitic minerals, were part icularly concentrated near or on root surfaces. These platy mineral pa rticles were not attached to the entire area, but only to certain area s of root surfaces. Therefore we report quantitative evidence for mine ralogical changes in the rhizosphere in soil environments.