Deciphering lead hypertolerance mechanisms in a population of the plant species Biscutella auriculata L. from a mining area: accumulation strategies and antioxidant defenses.

The uptake and distribution of Pb and the mechanisms involved in the metal tolerance have been investigated in a mine population of Biscutella auriculata. Seedlings were exposed to 125 uM Pb(NO3)2 for 15 days under semihydroponic conditions. The results showed an increase in the size of Pb-treated s...

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Detalles Bibliográficos
Autores: Olmedilla , Adela, Romero Puertas, María C, Sandalio González, Luisa M, Peco Palacios, Jesús Daniel, Higueras Higueras, Pablo León, Campos Gallego, Juan Antonio
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/39038
Acceso en línea:https://hdl.handle.net/10578/39038
Access Level:acceso abierto
Palabra clave:Biscutella auriculata
Oxidative stress
Phytoremediation
Descripción
Sumario:The uptake and distribution of Pb and the mechanisms involved in the metal tolerance have been investigated in a mine population of Biscutella auriculata. Seedlings were exposed to 125 uM Pb(NO3)2 for 15 days under semihydroponic conditions. The results showed an increase in the size of Pb-treated seedlings and symptoms of toxicity were not observed. ICP-OES analyses showed that Pb accumulation was restricted to root tissue. Imaging of Pb accumulation by dithizone histochemistry revealed the presence of the metal in vacuoles and cell wall in root cells. The accumulation of Pb in vacuoles could be stimulated by an increase in phytochelatin PC2 content. Pb did not promote oxidative damage and this is probably due the increase of antioxidative defenses. In the leaves, Pb produced a significant increase in superoxide dismutase activity, while in roots an increase in catalase and components of the Foyer– Halliwell–Asada cycle were observed. The results indicated that Biscutella auriculata has a high capacity to tolerate Pb and this is mainly due to a very efficient mechanism to sequester the metal in roots and a capacity to avoid oxidative stress. This species could therefore be very useful for phytostabilization and repopulation of areas contaminated with Pb.