20840510
not annotated - annotated - LINNAEUS only
Spatial distribution of arsenic and temporal variation of its concentration in rice.
* In order to gain insights into the transport and distribution of arsenic (As) in intact rice (Oryza sativa) plants and its unloading into the rice grain, we investigated the spatial distribution of As and the temporal variation of As concentration in whole rice plants at different growth stages. To the best of our knowledge, this is the first time that such a study has been performed. * Inductively coupled plasma mass spectroscopy (ICP-MS) and high-performance liquid chromatography (HPLC)-ICP-MS were used to analyze total As concentration and speciation. Moreover, synchrotron-based X-ray fluorescence (SXRF) was used to investigate in situ As distribution in the leaf, internode, node and grain. * Total As concentrations of vegetative tissues increased during the 2 wk after flowering. The concentration of dimethylarsinic acid (DMA) in the caryopsis decreased progressively with its development, whereas inorganic As concentration remained stable. The ratios of As content between neighboring leaves or between neighboring internodes were c. 0.6. SXRF revealed As accumulation in the center of the caryopsis during its early development and then in the ovular vascular trace. * These results indicate that there are different controls on the unloading of inorganic As and DMA; the latter accumulated mainly in the caryopsis before flowering, whereas inorganic As was mainly transported into the caryopsis during grain filling. Moreover, nodes appeared to serve as a check-point in As distribution in rice shoots.
Ann file
T1 Species 79 83 rice
N1 Reference T1 Taxonomy:4530
T2 Species 177 181 rice
N2 Reference T2 Taxonomy:4530
T3 Species 183 195 Oryza sativa
N3 Reference T3 Taxonomy:4530
T4 Species 231 235 rice
N4 Reference T4 Taxonomy:4530
T5 Species 346 350 rice
N5 Reference T5 Taxonomy:4530
T6 Species 1598 1602 rice
N6 Reference T6 Taxonomy:4530