Co-Segregation Analysis of Cadmium and Zinc Accumulation in Thlaspi caerulescens Interecotypic Crosses

• Published in: The New phytologist 2004-08, Vol.163 (2), p.299-312
• Main Authors: Zha, H. G., Jiang, R. F., Zhao, F. J., Vooijs, R., Schat, H., Barker, J. H. A., McGrath, S. P.
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Cadmium; cadmium (Cd); Crosses; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on plants and fungi; Fundamental and applied biological sciences. Psychology; genetic analysis; Hydroponics; hyperaccumulation; Hyperaccumulators; Phenotypes; Plant growth; Plants; Seedlings; Segregation; Thlaspi caerulescens; tolerance; Zinc; zinc (Zn)
• ISSN: 0028-646X; 1469-8137
• DOI: 10.1111/j.1469-8137.2004.01113.x

• Cadmium (Cd) hyperaccumulation in Thlaspi caerulescens varies among ecotypes. Here we investigated segregation of Cd and zinc (Zn) accumulation in F2crosses between high (Ganges) and low (Prayon) Cd-accumulating ecotypes. • Accumulation was measured in plants grown in compost treated with 5 and 100 mg kg-1Cd and Zn, respectively, and in hydroponics with 50 μM Zn and 10 or 50 μM Cd. Another hydroponic experiment examined the relationship between Cd tolerance and accumulation. • Parental phenotype distributions for shoot metal concentrations were distinct for Cd, but not consistent for Zn. Shoot Cd and Zn in F2s varied continuously, with significant transgression for Zn in all treatments. Shoot Cd correlated strongly with shoot manganese (Mn), and to a lesser degree with shoot Zn. Shoot Cd concentrations in the Cd nontolerant F2s were lower than, or similar to, those in the Cd-tolerant F2s. • We conclude that Cd and Zn accumulation is governed by multiple genes, and that Cd tolerance and accumulation are independent traits in T. caerulescens. Two uptake systems with distinctive affinities for Cd, Zn and Mn are proposed.