Dataset Information

Kinetin increases chromium absorption, modulates its distribution, and changes the activity of catalase and ascorbate peroxidase in Mexican Palo Verde.

ABSTRACT: This report shows, for the first time, the effectiveness of the phytohormone kinetin (KN) in increasing Cr translocation from roots to stems in Mexican Palo Verde. Fifteen-day-old seedlings, germinated in soil spiked with Cr(III) and (VI) at 60 and 10 mg kg(-1), respectively, were watered every other day for 30 days with a KN solution at 250 ?M. Samples were analyzed for catalase (CAT) and ascorbate peroxidase (APOX) activities, Cr concentration, and Cr distribution in tissues. Results showed that KN reduced CAT but increased APOX in the roots of Cr(VI)-treated plants. In the leaves, KN reduced both CAT and APOX in Cr(III) but not in Cr(VI)-treated plants. However, KN increased total Cr concentration in roots, stems, and leaves by 45%, 103%, and 72%, respectively, compared to Cr(III) alone. For Cr(VI), KN increased Cr concentrations in roots, stems, and leaves, respectively, by 53%, 129%, and 168%, compared to Cr(VI) alone. The electron probe microanalyzer results showed that Cr was mainly located at the cortex section in the root, and Cr distribution was essentially homogeneous in stems. However, proven through X-ray images, Cr(VI)-treated roots and stems had more Cr accumulation than Cr(III) counterparts. KN increased the Cr translocation from roots to stems.

SUBMITTER: Zhao Y

PROVIDER: S-EPMC4337997 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Kinetin increases chromium absorption, modulates its distribution, and changes the activity of catalase and ascorbate peroxidase in Mexican Palo Verde.

Zhao Yong Y Peralta-Videa Jose R JR Lopez-Moreno Martha L ML Ren Minghua M Saupe Geoffrey G Gardea-Torresdey Jorge L JL

Environmental science & technology 20101221 3

This report shows, for the first time, the effectiveness of the phytohormone kinetin (KN) in increasing Cr translocation from roots to stems in Mexican Palo Verde. Fifteen-day-old seedlings, germinated in soil spiked with Cr(III) and (VI) at 60 and 10 mg kg(-1), respectively, were watered every other day for 30 days with a KN solution at 250 μM. Samples were analyzed for catalase (CAT) and ascorbate peroxidase (APOX) activities, Cr concentration, and Cr distribution in tissues. Results showed th ...[more]

PMID: 21174467

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Dataset Information

Kinetin increases chromium absorption, modulates its distribution, and changes the activity of catalase and ascorbate peroxidase in Mexican Palo Verde.

Publications

Kinetin increases chromium absorption, modulates its distribution, and changes the activity of catalase and ascorbate peroxidase in Mexican Palo Verde.

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