TY - JOUR

T1 - Fractionation and chemical structure of dissolved organic matter in the rhizosphere associated with cadmium accumulation in tobacco lines (Nicotiana tabacum L.)

AU - Zhao, Ming

AU - Li, Tingxuan

AU - Yu, Haiying

AU - Zhang, Xizhou

AU - Zheng, Zicheng

AU - Wang, Yongdong

AU - Liu, Tao

AU - Gupta, Dharmendra K.

AU - Huang, Huagang

N1 - Funding Information: This study was carried out with the support of the Major Science and Technology Project of Sichuan Province (2018SZDZX0029), the Sichuan Key Research Program (2017SZ0188), and the National Key Research and Development Program of China (2018YFC1802605, 2018YFC1802606).

PY - 2020/5

Y1 - 2020/5

N2 - Reducing cadmium (Cd) accumulation in flue-cured tobacco is the main degree to reduce the harm of Cd to human health. In this study, a rhizobag experiment was conducted to investigate the characteristics of dissolved organic matter (DOM) in the rhizosphere of a low-Cd-accumulating tobacco line (RG11) and its role in the processes of Cd accumulation by plants. Cd concentrations in the roots and leaves of RG11 were 24.09–25.30 and 31.08–34.41% lower, respectively, than those of Yuyan5 under Cd stress. Cd exposure promoted DOM accumulation in the rhizosphere soils of the two tobacco lines. DOM concentrations in the rhizosphere soils of RG11 were 8.29–14.31% lower than those of Yuyan5 under Cd stress. RG11 presented less hydrophilic acid and hydrophilic base fractions, along with more hydrophobic acid and hydrophobic base fractions of DOM in the rhizosphere than those of Yuyan5 under Cd exposure. Fourier transform infrared spectroscopy results showed that RG11 exhibited less O–H, C–H, C=C, COO–, and C–O functional groups in rhizosphere DOM than those of Yuyan5 under Cd stress. Thus, the DOM in the rhizosphere of RG11 showed lower ability to solubilize Cd in soils, resulting in less Cd uptake by roots. This could be considered to be one of the important mechanisms of low Cd accumulation in leaves of RG11.

AB - Reducing cadmium (Cd) accumulation in flue-cured tobacco is the main degree to reduce the harm of Cd to human health. In this study, a rhizobag experiment was conducted to investigate the characteristics of dissolved organic matter (DOM) in the rhizosphere of a low-Cd-accumulating tobacco line (RG11) and its role in the processes of Cd accumulation by plants. Cd concentrations in the roots and leaves of RG11 were 24.09–25.30 and 31.08–34.41% lower, respectively, than those of Yuyan5 under Cd stress. Cd exposure promoted DOM accumulation in the rhizosphere soils of the two tobacco lines. DOM concentrations in the rhizosphere soils of RG11 were 8.29–14.31% lower than those of Yuyan5 under Cd stress. RG11 presented less hydrophilic acid and hydrophilic base fractions, along with more hydrophobic acid and hydrophobic base fractions of DOM in the rhizosphere than those of Yuyan5 under Cd exposure. Fourier transform infrared spectroscopy results showed that RG11 exhibited less O–H, C–H, C=C, COO–, and C–O functional groups in rhizosphere DOM than those of Yuyan5 under Cd stress. Thus, the DOM in the rhizosphere of RG11 showed lower ability to solubilize Cd in soils, resulting in less Cd uptake by roots. This could be considered to be one of the important mechanisms of low Cd accumulation in leaves of RG11.

KW - Cadmium

KW - Dissolved organic matter

KW - Fourier transform infrared spectroscopy

KW - Fractionation

KW - Low accumulation

KW - Tobacco

UR - http://www.scopus.com/inward/record.url?scp=85081739781&partnerID=8YFLogxK

U2 - 10.1007/s11356-020-08223-3

DO - 10.1007/s11356-020-08223-3

M3 - Article

C2 - 32162218

AN - SCOPUS:85081739781

VL - 27

SP - 17794

EP - 17803

JO - Environmental Science and Pollution Research

JF - Environmental Science and Pollution Research

SN - 0944-1344

IS - 15

ER -