title: Cadmium tolerance and accumulation by two species of Iris.
abstract: Seedlings of Iris lactea var. chinensis (Fisch.) Koidz. and I. tectorum Maxim. were subjected to 0-160 mg l(-1) Cd in hydroponic system and harvested after 42 days to determine effects on root and shoot dry mass. A subset of 16-day-old seedlings was exposed to 1000 mg l(-1) Cd to characterize sub-cellular localization of Cd in root cells. The Cd contents in the shoots of I. lactea var. chinensis reached 529 microg g(-1 )dry weight (dw) at 80 mg l(-1) Cd treatment and in the shoots of I. tectorum reached 232 microg g(-1) dw at 40 mg l(-1) Cd treatment, without showing signs of visible toxicity. The Cd contents in the shoots of both two test species exceeded 100 microg g(-1), the critical value of Cd hyperaccumulator. The indices of tolerance (ITs) of I. lactea var. chinensis were higher than those of I. tectorum under 10-160 mg l(-1)Cd stress. Sub-cellular localization of Cd in root cells was evaluated using transmission electron microscopy (TEM) and Cd deposits were found in the cell walls, in the cytoplasm and on the inner surface of xylem vessels in the root tip of I. lactea var. chinensis and I. tectorum. A few cells in the root tip of I. tectorum were necrotic. The results showed that the tolerance and accumulation of Cd by I. lactea var. chinensis were higher than those of I. tectorum, suggesting that I. lactea var. chinensis has potential application in phytoremediation.
authors: College of Life Science, Nanjing Agricultural University, Nanjing, PR China.
authors: Yu-Lin
authors: YL
authors: Han
authors: Hai-Yan
authors: HY
authors: Yuan
authors: Su-Zhen
authors: SZ
authors: Huang
authors: Zhi
authors: Z
authors: Guo
authors: Bing
authors: B
authors: Xia
authors: Jiguang
authors: J
authors: Gu
mesh_terms: D001673:Biodegradation, Environmental; D002104:Cadmium / Q000378:metabolism*; D031323:Iris Plant / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D018517:Plant Roots / Q000378:metabolism* / Q000648:ultrastructure; D036226:Seedlings / Q000254:growth & development
chemical_list: D002104:Cadmium
references: Plant Physiol. 1995 Dec;109(4):1427-1433
references: 12228679
references: Annu Rev Plant Physiol Plant Mol Biol. 1998 Jun;49:643-668
references: 15012249
references: Bioresour Technol. 2001 Jan;76(1):9-13
references: 11315815
references: Arch Environ Contam Toxicol. 2007 May;52(4):503-11
references: 17380236
references: J Plant Physiol. 1984 Jun;115(1):19-28
references: 23196083
references: Trends Plant Sci. 2004 Jan;9(1):7-9
references: 14729212
references: Environ Pollut. 1988;50(1-2):139-61
references: 15092656
references: Ecotoxicology. 2007 Apr;16(3):299-309
references: 17253159
references: Fresenius J Anal Chem. 2000 Sep-Oct;368(2-3):281-7
references: 11220593
references: Phytochemistry. 2002 May;60(2):153-62
references: 12009318
references: Ecotoxicology. 2004 Oct;13(7):637-46
references: 15673213
references: Huan Jing Ke Xue. 2005 May;26(3):167-71
references: 16124492