Claim · model-written summary
Excised-root nitrate reductase activity was higher with glucose than fructose after six hours.
- Taxon
- dwarf beant0
- Treatment
- glucosee0
- Outcome
- NRA of excised rootse0
- Direction
- highere0
- Qualifier
- after 6 h of nitrate nutritione0
- Comparator
- fructosee0
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleSettingValue
Verbatim
e0“the NRA of excised roots was also higher in the presence of glucose than in the presence of fructose after 6 h of nitrate nutrition”
t0“dwarf bean”
Title
Role of sugars in nitrate utilization by roots of dwarf bean
Charlotte H. Hänisch ten Cate; Hans Breteler Physiologia Plantarum 1981. doi:10.1111/j.1399-3054.1981.tb06045.x
Other claims from this paper (17)
- Association Sugar status did not influence the apparent induction pattern of nitrate uptake.
- Observation After 6 hours, steady-state nitrate uptake ranked intact above dark, ringed and excised plants.
- Observation After 6 hours, root nitrate reductase activity ranked intact above dark, ringed and excised plants.
- Intervention effect Exogenous sucrose restored nitrate reductase activity in excised roots to intact plant levels.
- Intervention effect Sucrose did not fully restore nitrate uptake in excised roots.
- Intervention effect Decapitation after nitrate pretreatment caused net uptake to decline and become negative after three hours.
- Intervention effect Exogenous fructose slowed the decline in net nitrate uptake after decapitation.
- Intervention effect Glucose rapidly stimulated nitrate uptake, sometimes within five minutes.
- Observation Glucose and fructose stimulated oxygen consumption equally.
- Observation Glucose and fructose stimulated labeled carbon dioxide release equally.
- Mechanism The authors propose a glucose-specific effect on nitrate uptake due to glucose presence rather than respiration.
- Observation There was no indicated differential glucose–fructose effect on nitrate reductase independent of nitrate uptake.
- Observation Nitrate-induced roots maintained constant nitrate reductase activity.
- Intervention effect Removing nitrate caused exponential nitrate reductase decay with a roughly 12-hour half-life in intact plants.
- Intervention effect Removing nitrate caused exponential nitrate reductase decay with a 5.5-hour half-life in excised roots.
- Observation Roots excised with nitrate present also had a 5.5-hour nitrate reductase decay half-life.
- Mechanism The authors infer that sugar status primarily sets the apparent nitrate reductase decay rate in excised roots.