Copper availability and bioavailability are controlled by rhizosphere pH in rape grown in an acidic Cu-contaminated soil
2009
Chaignon, Valérie | Quesnoit, Marie | Hinsinger, Philippe | Ecologie Fonctionnelle et Biogéochimie des Sols (Eco&Sols) ; Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Ecole Nationale Supérieure Agronomique de Montpellier (ENSA M)
Correspondance auteur: P. Hinsinger e-mail: philippe.hinsinger@supagro.inra.fr
显示更多 [+] 显示较少 [-]International audience
显示更多 [+] 显示较少 [-]英语. We evaluated how root-induced changes in rhizosphere pH varied and interacted with Cu availability and bioavailability in an acidic soil. Rape was grown on a Cu-contaminated acidic soil, which had been limed at 10 rates. Soil Cu bioavailability was not influenced by liming. However, liming significantly decreased CaCl2-extracted Cu for pH between 3.7 and 5.1. Little effect was found for pH above 5.1. For soil pH < 4.4, CaCl2-Cu contents were smaller in rhizosphere than uncropped soil. Rhizosphere alkalisation occurred at pH < 4.8, while acidification occurred at greater pH. This explained the changes of CaCl2-Cu in the rhizosphere at low pH and the absence of pH dependency of Cu bioavailability to rape. In addition, apoplastic Cu in roots increased with increasing soil pH, most probably as a result of increased dissociation and affinity of cell wall compounds for Cu
显示更多 [+] 显示较少 [-]