Comparison of DTPA and resin extractable soil Zn to plant Zn uptake

Hamilton, M.A. and Westermann, D.T. (1991) Comparison of DTPA and resin extractable soil Zn to plant Zn uptake. Communications in Soil Science and Plant Analysis. 25(5&6):517-528.

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Abstract

Extraction of soil zinc with routine chemical extractants does not
always reflect differences in Zn availability as detected by plant uptake. This study
was undertaken to explore and compare the use of an ion exchange resin and
diethylenetriaminepentaacetic acid (DTPA) for extracting soil Zn as related to plant
Zn uptake. Beans were grown in 1989 following differential cropping with corn
and beans or fallow in 1988 on a Portneuf silt loam near Kimberly, Idaho. Two
Zn fertilizer treatments were imposed across previous cropping treatments. A batch
method for determining resin extractable soil Zn was established.
Both plant Zn concentration and Zn uptake by beans in 1989 were significantly
higher in Zn fertilized than unfertilized treatments regardless of previous
crop; and higher in plots previously cropped with corn than beans or fallow,
regardless of Zn treatment. DTPA and resin extractable soil Zn were significantly
higher in Zn fertilized plots compared to unfertilized plots but did not differ
between previous cropping treatments. Resin and DTPA extractable soil Zn concentrations
were positively correlated. Resin extracted soil Zn correlated better with
plant Zn concentration and Zn uptake throughout the growing season than DTPA
extracted soil Zn, particularly in plots that had been fallowed or previously cropped
with corn. Resin may be extracting labile soil Zn not extracted with DTPA and,
therefore, be better simulating plant uptake. Both extraction methods correlated
better with Zn uptake when evaluated within cropping treatments, emphasizing the
need to consider previous crop when calibrating soil tests.

Item Type:	Article
NWISRL Publication Number:	0732
Subjects:	Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:53
Last Modified:	09 Dec 2016 18:37
Item ID:	548
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/548