INVESTIGADORES
RAPISARDA Viviana Andrea
congresos y reuniones científicas
Título:
Histochemical localization of cadmium in rangpur lime (Citrus limonia L. Osbeck) roots
Autor/es:
PODAZZA, G.; RAPISARDA, V. A.; GONZALEZ, J. C.; ARIAS, M. E.; PRADO, F. E.
Lugar:
Carlos Paz (Córdoba)
Reunión:
Congreso; XLIV Reunión Anual de SAIB; 2008
Institución organizadora:
SAIB
Resumen:
The first manifestation of Cd2+ toxicity in plants takes place at radicular level because root is the first organ interacting with metals. Rangpur lime is used as a lemon rootstock in many countries and little is known respect to its response to heavy metals. The aim of this work was to study the distribution and effect of different Cd2+ concentrations in roots of Rangpur lime seedlings at the level of the absorption zone. Thirty five days old seedlings were transferred to 0 (control), 5 and 10 ìM CdCl2 in hydroponic culture for 7 days . Excised roots were fixed and cut into semithin sections (2 cm upper the apex). For microscopic analyses, sections were clarified with NaClO and stained with specific dyes: 2-(8-quinolylazo)-4,5-diphenylimidazole (cadmium), toluidine blue (lignin, pectin), and Sudan IV (suberin). No changes were found in total root and vascular cylinder diameters or epidermis and exodermis thickness. Cd2+ was detected in both exodermis and vascular cylinder of roots treated with 5 and 10 ìM CdCl2. Lignin was detected in the xylem of both control and Cd2+ treated roots, but in the last one the colour intensity was lower. Pectin was only detected in the cortex of Cd-exposed roots, while suberin was detected in both exodermis and endodermis of control and 5 µM treated roots. Results indicated that Cd2+ affected mainly the cell wall structures but not the root morphology.