Details
| Original language | English |
|---|---|
| Pages (from-to) | 1129-1136 |
| Number of pages | 8 |
| Journal | Plant physiology |
| Volume | 128 |
| Issue number | 3 |
| Publication status | Published - 1 Mar 2002 |
| Externally published | Yes |
Abstract
The influence of urease activity on N distribution and losses after foliar urea application was investigated using wild-type and transgenic potato (Solanum tuberosum cv Désirée) plants in which urease activity was down-regulated. A good correlation between urease activity and 15N urea metabolism (NH3 accumulation) was found. The general accumulation of ammonium in leaves treated with urea indicated that urease activity is not rate limiting, at least initially, for the assimilation of urea N by the plant. It is surprising that there was no effect of urease activity on either N losses or 15N distribution in the plants after foliar urea application. Experiments with wild-type plants in the field using foliar-applied 15N urea demonstrated an initial rapid export of N from urea-treated leaves to the tubers within 48 h, followed by a more gradual redistribution during the subsequent days. Only 10% to 18% of urea N applied was lost (presumably because of NH3 volatilization) in contrast to far greater losses reported in several other studies. The pattern of urease activity in the canopy was investigated during plant development. The activity per unit protein increased up to 10-fold with leaf and plant age, suggesting a correlation with increased N recycling in senescing tissues. Whereas several reports have claimed that plant urease is inducible by urea, no evidence for urease induction could be found in potato.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Physiology
- Biochemistry, Genetics and Molecular Biology(all)
- Genetics
- Agricultural and Biological Sciences(all)
- Plant Science
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In: Plant physiology, Vol. 128, No. 3, 01.03.2002, p. 1129-1136.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Leaf urea metabolism in potato. Urease activity profile and patterns of recovery and distribution of 15N after foliar urea application in wild-type and urease-antisense transgenics
AU - Witte, Claus Peter
AU - Tiller, Sarah A.
AU - Taylor, Mark A.
AU - Davies, Howard V.
PY - 2002/3/1
Y1 - 2002/3/1
N2 - The influence of urease activity on N distribution and losses after foliar urea application was investigated using wild-type and transgenic potato (Solanum tuberosum cv Désirée) plants in which urease activity was down-regulated. A good correlation between urease activity and 15N urea metabolism (NH3 accumulation) was found. The general accumulation of ammonium in leaves treated with urea indicated that urease activity is not rate limiting, at least initially, for the assimilation of urea N by the plant. It is surprising that there was no effect of urease activity on either N losses or 15N distribution in the plants after foliar urea application. Experiments with wild-type plants in the field using foliar-applied 15N urea demonstrated an initial rapid export of N from urea-treated leaves to the tubers within 48 h, followed by a more gradual redistribution during the subsequent days. Only 10% to 18% of urea N applied was lost (presumably because of NH3 volatilization) in contrast to far greater losses reported in several other studies. The pattern of urease activity in the canopy was investigated during plant development. The activity per unit protein increased up to 10-fold with leaf and plant age, suggesting a correlation with increased N recycling in senescing tissues. Whereas several reports have claimed that plant urease is inducible by urea, no evidence for urease induction could be found in potato.
AB - The influence of urease activity on N distribution and losses after foliar urea application was investigated using wild-type and transgenic potato (Solanum tuberosum cv Désirée) plants in which urease activity was down-regulated. A good correlation between urease activity and 15N urea metabolism (NH3 accumulation) was found. The general accumulation of ammonium in leaves treated with urea indicated that urease activity is not rate limiting, at least initially, for the assimilation of urea N by the plant. It is surprising that there was no effect of urease activity on either N losses or 15N distribution in the plants after foliar urea application. Experiments with wild-type plants in the field using foliar-applied 15N urea demonstrated an initial rapid export of N from urea-treated leaves to the tubers within 48 h, followed by a more gradual redistribution during the subsequent days. Only 10% to 18% of urea N applied was lost (presumably because of NH3 volatilization) in contrast to far greater losses reported in several other studies. The pattern of urease activity in the canopy was investigated during plant development. The activity per unit protein increased up to 10-fold with leaf and plant age, suggesting a correlation with increased N recycling in senescing tissues. Whereas several reports have claimed that plant urease is inducible by urea, no evidence for urease induction could be found in potato.
UR - http://www.scopus.com/inward/record.url?scp=0036006064&partnerID=8YFLogxK
U2 - 10.1104/pp.010506
DO - 10.1104/pp.010506
M3 - Article
C2 - 11891267
AN - SCOPUS:0036006064
VL - 128
SP - 1129
EP - 1136
JO - Plant physiology
JF - Plant physiology
SN - 0032-0889
IS - 3
ER -