Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen.
The C 3 grass Poa trivialis and the C 4 grass Panicum maximum were grown in sand culture and received a complete nutrient solution with nitrogen supplied as 1.5 mol m -3 NH 4NO 3. 15 N tracer techniques were used to quantify the relative use of root uptake and mobilization in supplying nitrogen to growing leaves in intact plants which either continued to receive nitrogen or which received the complete nutrient solution without nitrogen. The allocation of both 15 N-labelled nitrogen uptake and unlabelled mobilized nitrogen indicated that, under their conditions of growth, the sink strength of growing leaves was relatively greater in P. maximum than P. trivialis. The supply of nitrogen by mobilization to side tillers of P. trivialis was completely stopped as the external nitrogen supply was reduced, whilst in P. maximum some allocation of mobilized nitrogen to side tillers, roots and growing leaves was maintained. In both plant species receiving an uninterrupted supply of nitrogen the allocation pattern of mobilized nitrogen differed from that of nitrogen derived from root uptake. Differences exist in the degree to which P. trivialis and P. maximum utilized uptake and mobilization to supply nitrogen to the growing leaves. In P. trivialis roots were always a net sink of mobilized nitrogen, irrespective of the external nitrogen supply. In P. maximum, roots were a net sink of mobilized nitrogen when external nitrogen was withdrawn, but exhibited both source and sink behaviour when nitrogen supply was continued.
Main Authors: | , , |
---|---|
Other Authors: | |
Format: | Artigo de periódico biblioteca |
Language: | pt_BR por |
Published: |
2002-12-04
|
Subjects: | Leaf growth, N mobilization, N uptake, C3, C4., Panicum Maximum., Poa trivialis., |
Online Access: | http://www.alice.cnptia.embrapa.br/alice/handle/doc/41868 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
id |
dig-alice-doc-41868 |
---|---|
record_format |
koha |
spelling |
dig-alice-doc-418682017-08-15T21:52:17Z Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen. SANTOS, P. M. THORTON, B. CORSI, M. MOACYR CORSI, USP-ESALQ. BARRY THORNTON, The Macaulay Institute, Craigiebuckler PATRICIA MENEZES SANTOS, CPPSE Leaf growth N mobilization N uptake C3 C4. Panicum Maximum. Poa trivialis. The C 3 grass Poa trivialis and the C 4 grass Panicum maximum were grown in sand culture and received a complete nutrient solution with nitrogen supplied as 1.5 mol m -3 NH 4NO 3. 15 N tracer techniques were used to quantify the relative use of root uptake and mobilization in supplying nitrogen to growing leaves in intact plants which either continued to receive nitrogen or which received the complete nutrient solution without nitrogen. The allocation of both 15 N-labelled nitrogen uptake and unlabelled mobilized nitrogen indicated that, under their conditions of growth, the sink strength of growing leaves was relatively greater in P. maximum than P. trivialis. The supply of nitrogen by mobilization to side tillers of P. trivialis was completely stopped as the external nitrogen supply was reduced, whilst in P. maximum some allocation of mobilized nitrogen to side tillers, roots and growing leaves was maintained. In both plant species receiving an uninterrupted supply of nitrogen the allocation pattern of mobilized nitrogen differed from that of nitrogen derived from root uptake. Differences exist in the degree to which P. trivialis and P. maximum utilized uptake and mobilization to supply nitrogen to the growing leaves. In P. trivialis roots were always a net sink of mobilized nitrogen, irrespective of the external nitrogen supply. In P. maximum, roots were a net sink of mobilized nitrogen when external nitrogen was withdrawn, but exhibited both source and sink behaviour when nitrogen supply was continued. 2011-04-09T21:34:25Z 2011-04-09T21:34:25Z 2002-12-04 2002 2011-04-10T11:11:11Z Artigo de periódico Journal of Experimental Botany, v.53, n.378, p.2167-2176, nov. 2002. http://www.alice.cnptia.embrapa.br/alice/handle/doc/41868 10.1093/jxb/erf066 pt_BR por openAccess |
institution |
EMBRAPA |
collection |
DSpace |
country |
Brasil |
countrycode |
BR |
component |
Bibliográfico |
access |
En linea |
databasecode |
dig-alice |
tag |
biblioteca |
region |
America del Sur |
libraryname |
Sistema de bibliotecas de EMBRAPA |
language |
pt_BR por |
topic |
Leaf growth N mobilization N uptake C3 C4. Panicum Maximum. Poa trivialis. Leaf growth N mobilization N uptake C3 C4. Panicum Maximum. Poa trivialis. |
spellingShingle |
Leaf growth N mobilization N uptake C3 C4. Panicum Maximum. Poa trivialis. Leaf growth N mobilization N uptake C3 C4. Panicum Maximum. Poa trivialis. SANTOS, P. M. THORTON, B. CORSI, M. Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen. |
description |
The C 3 grass Poa trivialis and the C 4 grass Panicum maximum were grown in sand culture and received a complete nutrient solution with nitrogen supplied as 1.5 mol m -3 NH 4NO 3. 15 N tracer techniques were used to quantify the relative use of root uptake and mobilization in supplying nitrogen to growing leaves in intact plants which either continued to receive nitrogen or which received the complete nutrient solution without nitrogen. The allocation of both 15 N-labelled nitrogen uptake and unlabelled mobilized nitrogen indicated that, under their conditions of growth, the sink strength of growing leaves was relatively greater in P. maximum than P. trivialis. The supply of nitrogen by mobilization to side tillers of P. trivialis was completely stopped as the external nitrogen supply was reduced, whilst in P. maximum some allocation of mobilized nitrogen to side tillers, roots and growing leaves was maintained. In both plant species receiving an uninterrupted supply of nitrogen the allocation pattern of mobilized nitrogen differed from that of nitrogen derived from root uptake. Differences exist in the degree to which P. trivialis and P. maximum utilized uptake and mobilization to supply nitrogen to the growing leaves. In P. trivialis roots were always a net sink of mobilized nitrogen, irrespective of the external nitrogen supply. In P. maximum, roots were a net sink of mobilized nitrogen when external nitrogen was withdrawn, but exhibited both source and sink behaviour when nitrogen supply was continued. |
author2 |
MOACYR CORSI, USP-ESALQ. |
author_facet |
MOACYR CORSI, USP-ESALQ. SANTOS, P. M. THORTON, B. CORSI, M. |
format |
Artigo de periódico |
topic_facet |
Leaf growth N mobilization N uptake C3 C4. Panicum Maximum. Poa trivialis. |
author |
SANTOS, P. M. THORTON, B. CORSI, M. |
author_sort |
SANTOS, P. M. |
title |
Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen. |
title_short |
Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen. |
title_full |
Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen. |
title_fullStr |
Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen. |
title_full_unstemmed |
Nitrogen dynamics in the intact grasses Poa trivialis and Panicum maximum receiving contrastaing supplies of nitrogen. |
title_sort |
nitrogen dynamics in the intact grasses poa trivialis and panicum maximum receiving contrastaing supplies of nitrogen. |
publishDate |
2002-12-04 |
url |
http://www.alice.cnptia.embrapa.br/alice/handle/doc/41868 |
work_keys_str_mv |
AT santospm nitrogendynamicsintheintactgrassespoatrivialisandpanicummaximumreceivingcontrastaingsuppliesofnitrogen AT thortonb nitrogendynamicsintheintactgrassespoatrivialisandpanicummaximumreceivingcontrastaingsuppliesofnitrogen AT corsim nitrogendynamicsintheintactgrassespoatrivialisandpanicummaximumreceivingcontrastaingsuppliesofnitrogen |
_version_ |
1756015101659316224 |