Zinc (hyper)accumulation in Cardamine waldsteinii: from discovery in the herbarium to validation in the field

Abstract

X-ray Fluorescence Spectroscopy (XRF) is a non-destructive analytical technique that has recently been developed as a tool for high throughput screening for the discovery of trace element hyperaccumulator species in herbarium collections. Herbarium XRF analysis was undertaken of representatives of the Brassicaceae family in the two herbaria in Belgrade (Serbia). This was coupled to field collection and chemical analysis of new samples of Cardamine waldsteinii. The data revealed a potentially new zinc hyperaccumulator species, C. waldsteinii, with 3050 mg kg⁻¹ Zn in its leaves. This compares to 2210 mg kg⁻¹ in the leaves of this species collected from the field. These values are below the notional hyperaccumulation threshold for zinc but are nevertheless unusual. The remarkably high accumulation factor for zinc are suggestive of the exceptional potential of C. waldsteinii for zinc uptake, even in non-metalliferous, zinc-deficient soils. We recommend following up this study with experimental investigations on C. waldsteinii to elucidate its ecophysiology and its zinc tolerance and accumulation characteristics.

Keywords:

• Metallophyte
• hypertolerance
• Brassicaceae
• herbarium specimens
• X-ray fluorescence spectroscopy

Acknowledgments

The authors would like to thank Dr. Marjan Niketić and Dr. Uroš Buzurović (curators in BEO), Dr. Snežana Vukojičić (curator in BEOU), and Dr. Vanessa Invernon (collection manager in MNHN) for help with herbarium collection, and Mrs. Milka Adžić for help in field investigation.

Authors’ contributions

KJ, TM, and GE created a concept and collected the data; KJ prepared the original draft; GA performed the laboratory analyses; TM, AVDE, AJMB, GT, and GE discussed the results and contributed to the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia under grants 451-03-47/2023-01/ 200178 and 451-03-47/2023-01/ 200019 and Serbian-French Bilateral Project under grant 337-00-08/2020-09/20, the Ministry of Europe and Foreign Affairs (MEAE), the Ministry of Higher Education and Research (MESR) of the Republic of France and Econick.