Phytostabilization of cadmium contaminated soils by Lupinus uncinatus Schldl.

Abstract

Phytoremediation offers the benefits of being in situ, low cost and environmentally sustainable. Lupinus species is starting to generate interest for phytoremediation of soils showing intermediate metal pollution. The aim of this study was to explore the accumulating behavior and tolerance of Lupinus uncinatus Schldl. towards increasing Cd concentrations in soil. For this purpose the effects of different Cd treatments on plant growth, survival, metal tolerance, Cd accumulation and distribution in various plant organs were investigated. An 18 week pot trial was performed under greenhouse conditions. Cd was added as CdCl2.2.1/2H2O at the rate of 0, 3, 6 and 9 mg Cd/kg soil at three different occasions (after 4th, 12th and 15th week of plant growth) with four replicates. The Cd treatments applied, thus, were 9, 18 and 27 mg/kg. Cd inhibited plant height and number of leaves and induced a significant change in dry matter yield of roots, stems and leaves. Metal tolerance indices of 88, 82 and 49% were obtained for 9, 18 and 27 mg Cd/kg treatments. The maximal shoot Cd concentration (stem+leaves) of 540 mg Cd/kg dry matter was found at 27 mg Cd/kg treatment. The poor translocation of Cd from roots to shoot was evident from shoot:root ratios

Capacidad fitorremediadora de cinco especies altoandinas de suelos contaminados con metales pesados

“…Estudios realizados en especies de los géneros Lupinus, Solanum y Brassica siguieron comportamientos similares a los previamente descritos, tal fue el caso de Lupinus uncinatus, el cual cuando fue evaluado con diferentes concentraciones de cadmio aplicado al suelo, presentó inhibición del crecimiento en longitud de planta y en número de hojas; consecuentemente, el cadmio también influyó significativamente en el rendimiento de la materia seca en raíces, hojas y tallos (Ehsan et al 2009).…”

Zinc and cadmium accumulation by Lupinus uncinatus Schldl. grown in nutrient solution

“…This may suggest that the observed pattern of Cd partitioning is a plant strategy to counter toxicity as also suggested by Zornoza et al (2002). The Cd uptake in the lupin roots serves to offer the benefit of metal phytostabilization (Ehsan et al 2009). …”

“…Overall, the results support the hypothesis that L. uncinatus could be used in the combined strategies to recover Zn-and Cd-contaminated soils. The use of L. uncinatus could associate the advantages of using leguminous plants and the efficiency in phytostabilization (Ehsan et al 2009) as also demonstrated for other trace elements in the case of white lupin (Vazquez et al 2006;Esteban et al 2008) and also in case of other plants such as Viguiera dentata, Parthenium bipinnatifidum, Flaveria angustifolia, F. trinervia, and Sporobolus indicus which could be used to vegetate soils with large amounts of As, Cu, Pb, and Zn (Franco-Hernández et al 2010). Its efficiency in accumulating Cd in the roots, with very low translocation rate to the shoots, could make it a good choice in phytostabilization, preventing leaking of Cd from contaminated soils.…”

“…Ximenez-Embun et al (2001) reported that L. albus, L. luteus, L. angustifolius, and L. hispanicus were able to grow under extreme conditions (wastewater, pH lower than 2) and to remove 98 % of the initial amount of toxic metals present in the sample. In a pot study, we also found that L. uncinatus could be used for phytostabilization of Cd-contaminated soils (Ehsan et al 2009). However, to the best of our knowledge, no information is available concerning metal accumulation in L. uncinatus in nutrient solution.…”

How a phosphorus‐acquisition strategy based on carboxylate exudation powers the success and agronomic potential of lupines (Lupinus, Fabaceae)

“…Lupinus chamissonis enhances biodegradation of hydrocarbon‐contaminated groundwater, possibly by stimulating the hydrocarbon‐degrading microorganisms in the soil (Hoffman, 2004). Lupines such as L. uncinatus Schltdl., a species native to Mexico (Alderete‐Chavez et al, 2008) have also been studied for their potential for in situ metal phytostabilization (or immobilization), which helps prevent erosion, reduce airborne movement, and leaching of pollutants (Ehsan et al, 2009), allowing plants with lower uptake of metals to be used to prevent transfer into the environment. Lupinus albus is suitable for the initial phytoimmobilisation of heavy metals in a calcareous soil with high levels of zinc and lead (Martínez‐Alcalá et al, 2009).…”