Record ID No. |
2266 |
Author(s) |
Straczek A., Wannijn J., VanHees M., Thijs H., Thiry Y. , 2009 |
Affiliation |
Belgium Nucl Res Ctr SCK CEN, Fdn Publ Util, Radiat Protect Res Dept, Radioecol Sect, Boeretang 200, B-2400 Mol, BELGIUM |
Title |
Tolerance of hairy roots of carrots to U chronic exposure in a standardized in vitro device |
Source. Vol.(no):Page |
Environmental and Experimental Botany. 65(1): 82-89p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Biochemistry |
Sub-subjects |
Miscellaneous |
Country |
Belgium, Europe |
Abstracts |
In soil, high variability of U bioavailability results in large range of apparent U toxic levels for plants. U toxicity on hairy roots of carrot was studied in nutrient gel with a standardized in vitro device. After exposure to 2.5 and 20 mg UL-1 for 34 days, U concentration ranged between 4 and 563 mg U kg(-1) fresh weight which was in good accordance with U accumulation by roots of plant from contaminated soils. Threshold of U toxicity for root length decreased with time and a transient hormesis occurred for exposure to 2.5 and 5 mg UL-1. After 34 days and with root length as endpoint, significant toxicity appeared at a gel contamination level above 7.5 mg UL-1 corresponding to a maximum U concentration in the liquid phase of 0.8 mg L-1. The calculated EC50 for root length as a function of gel contamination was 9.4 mg UL-1. Lower threshold and EC50 were observed for biomass as endpoint (resp. 5 and 7.3 mg UL-1). The low values observed in this study could result from high sensitivity of carrot to U, high bioavailability of U in gel or absence of interferences with microorganisms. This in vitro device appeared adapted to study toxicity of U to plant roots in optimal conditions of both exposure and observations and is recommended to examine further physiological processes and the influence of microorganism interactions. |