Abstract
Concentrations of total N, ninhydrin-positive compounds, and monosubstituted guanidino compounds were determined in current and 1-year-old foliage and twigs, and in roots of 3-year-old Douglas fir (Pseudotsugamenziesii (Mirb.) Franco.). These plants were grown in a trial where levels of N (0, 255, and 675 kg N/ha), and sources of N (nitrate, ammonium, and urea) had been applied factorially. N fertilizer treatment increased soluble N levels by as much as 19 times control values, whereas total N was increased at most 40%. Total N in 1-year-old foliage, current twigs, and roots, and guanidino compounds in 1-year-old twigs were consistently different for different N treatment levels. Sixty percent of the variance in plant size measurements could be explained by six N measurements, including total N, in multiple regression.In a second experiment, concentrations of arginine and proline, in addition to concentrations of ninhydrin-positive compounds, guanidino compounds, and total N, were determined in foliage of 3-year-old Douglas fir grown in growth chambers at 10 and 21 °C. Four provenances, to which three moisture-stress treatments were factorially applied, were represented at each temperature. Concentration of soluble N compounds was higher at 21 °C than at 10 °C, but not concentration of total N. Moisture stress increased concentration of soluble N compounds, in particular proline, and there were some differences between provenances in concentrations of soluble N compounds and total N.
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Claims 9
Claim · model-written summary
N fertilizer increased soluble N up to 19 times control values.
- Taxon
- Douglas Fir
Pseudotsuga menziesiit0 - Treatment
- N fertilizer treatmente0
- Outcome
- soluble N levelse0
- Direction
- increasede0
- Value
- 19 timese0
- Comparator
- control valuese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N fertilizer treatment increased soluble N levels by as much as 19 times control values”
t0“Douglas Fir”
Claim · model-written summary
N fertilizer increased total N at most 40%.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Outcome
- total Ne0
- Direction
- increasede0
- Value
- 40%e0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“total N was increased at most 40%”
t0“Douglas Fir”
Claim · model-written summary
Total N in one-year foliage, current twigs and roots differed across N treatments.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Organ / stage
- 1-year-old foliage, current twigs, and rootse0
- Treatment
- N treatment levelse0
- Outcome
- Total Ne0
- Direction
- differente0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Total N in 1-year-old foliage, current twigs, and roots, and guanidino compounds in 1-year-old twigs were consistently different for different N treatment levels”
t0“Douglas Fir”
Claim · model-written summary
Guanidino compounds in one-year twigs differed across N treatments.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Organ / stage
- 1-year-old twigse0
- Treatment
- N treatment levelse0
- Outcome
- guanidino compoundse0
- Direction
- differente0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“guanidino compounds in 1-year-old twigs were consistently different for different N treatment levels”
t0“Douglas Fir”
Claim · model-written summary
Six N measurements explained 60% of variance in plant size.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Compound
- total Ne0
- Outcome
- variance in plant size measurementse0
- Value
- Sixty percente0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sixty percent of the variance in plant size measurements could be explained by six N measurements, including total N, in multiple regression”
t0“Douglas Fir”
Claim · model-written summary
Soluble N compounds were higher at 21 °C than 10 °C.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Treatment
- 21 °Ce0
- Outcome
- Concentration of soluble N compoundse0
- Direction
- highere0
- Comparator
- 10 °Ce0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Concentration of soluble N compounds was higher at 21 °C than at 10 °C”
t0“Douglas Fir”
Claim · model-written summary
Total N concentration was not higher at 21 °C than 10 °C.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Treatment
- 21 °Ce0
- Outcome
- concentration of total Ne0
- Direction
- no_changeinferrede0
- Comparator
- 10 °Ce0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Concentration of soluble N compounds was higher at 21 °C than at 10 °C, but not concentration of total N”
t0“Douglas Fir”
Claim · model-written summary
Moisture stress increased soluble N compounds, particularly proline.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Treatment
- Moisture stresse0
- Outcome
- concentration of soluble N compounds, in particular prolinee0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Moisture stress increased concentration of soluble N compounds, in particular proline”
t0“Douglas Fir”
Claim · model-written summary
Provenances differed in soluble N compound and total N concentrations.
- Taxon
- Douglas FirPseudotsuga menziesiit0
- Material
- provenancese0
- Outcome
- concentrations of soluble N compounds and total Ne0
- Direction
- differencese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“there were some differences between provenances in concentrations of soluble N compounds and total N”
t0“Douglas Fir”
The same questions in other papers
fertilization · nutrient: content · Pseudotsuga menziesii (Douglas-fir)Positive and negative results
2 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- negative
- positive
1 paper more in this group
See all 5 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.