title: Impact of osmoregulation on the differences in Cd accumulation between two contrasting edible amaranth cultivars grown on Cd-polluted saline soils.
abstract: This study aimed to investigate the difference of osmoregulation between two edible amaranth cultivars, Liuye (high Cd accumulator) and Quanhong (low Cd accumulator), under salinity stress and determine the effects of such difference on Cd accumulation. A pot experiment was conducted to expose the plants to sewage-irrigated garden soil (mean 2.28 mg kg-1Cd) pretreated at three salinity levels. Under salinity stress, the concentrations of Cd in the two cultivars were significantly elevated compared with those in the controls, and the Cd concentration in Liuye was statistically higher than that in Quanhong (p < 0.05). Salinity-induced osmoregulation triggered different biogeochemical processes involved in Cd mobilization in the rhizosphere soil, Cd absorption, and translocation by the two cultivars. Rhizosphere acidification induced by an imbalance of cation over anion uptake was more serious in Liuye than in Quanhong, which obviously increased soil Cd bioavailability. Salinity-induced injuries in the cell wall pectin and membrane structure were worse in Liuye than in Quanhong, increasing the risk of Cd entering the protoplasts. The chelation of more cytoplasmic Cd2+with Cl-ions in the roots of Liuye promoted Cd translocation into the shoots. Furthermore, the less organic solutes in the root sap of Liuye than in that of Quanhong also favored Cd translocation into the shoots. Hence, osmoregulation processes can be regarded as important factors in reducing Cd accumulation in crop cultivars grown on saline soils.
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Department of Ecology, Jinan University, Guangzhou, 510632, China.
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Xu
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, Guangzhou, 510632, China. Electronic address: liqusheng@21cn.com.
authors.forename: Qu-Sheng
authors.initials: QS
authors.lastname: Li
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, Guangzhou, 510632, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yang
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, Guangzhou, 510632, China.
authors.forename: Han-Jie
authors.initials: HJ
authors.lastname: Ye
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, Guangzhou, 510632, China.
authors.forename: Zi-Shuo
authors.initials: ZS
authors.lastname: Chen
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, Guangzhou, 510632, China.
authors.forename: Shi-Hong
authors.initials: SH
authors.lastname: Guo
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, Guangzhou, 510632, China.
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Wang
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China; Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, Guangzhou, 510632, China.
authors.forename: Bao-Yan
authors.initials: BY
authors.lastname: He
authors.affiliation: Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou, 510632, China.
authors.forename: Eddy Y
authors.initials: EY
authors.lastname: Zeng
mesh_terms: D027721:Amaranthus / Q000254:growth & development / Q000378:metabolism*; D002104:Cadmium / Q000032:analysis*; D064587:Osmoregulation; D018517:Plant Roots / Q000378:metabolism*; D058441:Rhizosphere; D054712:Salinity; D012965:Sodium Chloride / Q000032:analysis; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D013045:Species Specificity
chemical_list: D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; D012965:Sodium Chloride
keywords: Cadmium accumulation; Edible amaranth; Osmoregulation; Salinity stress