Abstract
Chromium released into the environment from industrial activities has become an important environmental concern. Silene vulgaris has been proven to be tolerant to many heavy metals, so it is considered an interesting species in the revegetation and restoration of polluted soils, but no information is available about its response to Cr. The objective of this work was to study uptake and influence on plant growth of Cr(III) and Cr(VI) in six genotypes (four hermaphrodites and two females) of S. vulgaris from different sites of Madrid (Spain). Plants were treated for 12 days with 60 µM of Cr(III) or Cr(VI) in semihydroponics. Dry weights, soil-plant analysis development values (SPAD) reading with chlorophylls and micronutrient and total Cr concentrations were determined. Metal uptake was higher in presence of Cr(VI) than of Cr(III) and poorly translocated to the shoots. In both cases S. vulgaris did not show visual toxicity symptoms, biomass reduction, or differences among SPAD values as consequence of Cr additions. However genotypes SV36 and SV38 showed Fe and Mn imbalance. This is the first report on the relatively good performance of hermaphrodite and female S. vulgaris genotypes in Cr uptake and physiological traits, but further studies will be necessary to elucidate the mechanisms by which the gender may influence these variables. S. vulgaris presented high diversity at genotypic level; the treatment with hexavalent Cr increased the differences among genotypes so the use of cuttings from an homogeneous genotype seems to be an adequate method for the study of this species.
Highlights
Chromium is a heavy metal used on a large scale in industry
The objectives of this study were: a) to assess whether the presence of low concentrations of Cr(III) or Cr(VI) in nutrient solution led to differences in Cr uptake by S. vulgaris at genotype level; b) to evaluate the effectiveness of the genotypes using the classical approach of the growth efficiency of wild plants based on micronutrient status and state of chlorophylls
The genotypes of S. vulgaris grown in nutrient solution did not show any visual or physiological toxicity symptoms after being treated with 60 μM of Cr(III) or Cr(VI) during 12 days
Summary
Chromium is a heavy metal used on a large scale in industry. Cr contamination does not pose a global risk, it could be a serious problem for the local environment (Bielicka et al, 2005). Once it enters the environment, its toxicity is determined to a large extent by its chemical form, which is responsible for its mobility and bioavailability (Kotas & Stasicka, 2000). The active-redox Cr(VI) is more water soluble and more bioavailable than Cr(III), and it has been classified as carcinogen of Group A by the EPA (United States Environmental Protection Agency; USEPA, 1998). The role of Cr(III) as essential anion in mammals and plants is under question because it seems to be toxic at higher doses than Cr(VI) (Levina & Lay, 2008)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
