Abstract
Nicotiana tabacum L. cv. Ky-14 plants were grown in an intermittently irrigated gravel culture system in a greenhouse. The nutrient variables were either Mo (0 to 0.66 μeq/l) or Mo (0 and 0.33 μeq/l) plus SO 4 2− (0 to 0.50 meq/l). About 45 days after initiating the treatments, the plants were harvested and separated into leaves, midribs, stalk epidermis, stalk xylem–phloem, and stalk pith for Mo, S, NO 3 − , total N, and nitrate reductase (NR) (EC 1.6.6.1) activity assay. Other plants were grown in complete Hoagland's solution (i.e., 0.66 μeq Mo/l and 0.50 meq SO 4 2− /l) for all nutrient elements and used for determinations of canopy and seasonal profiles of NR activity.Molybdenum concentration in all plant parts increased with increasing solution Mo concentration. Sulfate drastically reduced the concentration of Mo, and the inhibition was essentially equal in all plant parts. Greatest reduction of Mo occurred with the first increment of SO 4 2− (0.05 meq/l), with little effects from further additions of SO 4 2− . The data suggest that the inhibitory effects of SO 4 2− on Mo content occur primarily during the absorption process, with some antagonistic mechanism involved during translocation from roots to leaves. Molybdenum was not inhibitory to S accumulation. Contents of Mo and S in leaves were greater than in any other plant part.NR activity generally increased from bottom to top leaves. About 60% of the NR in the plant occurred in the leaves. The canopy profiles suggest that the recent, completely open leaf (7–9 in. long) and the second and third leaves below it could be sampled for maximum NR activity for NO 3 − reduction experiments. Sulfate nutrition increased NR activity, as a result of increased NR synthesis, while Mo nutrition was without effect on NR in these experiments. The NO 3 − content was not affected by SO 4 2− , but NO 3 − increased in the absence of Mo.
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Claims 13
Claim · model-written summary
Plant molybdenum concentration increased as solution molybdenum increased.
- Taxon
- Nicotiana tabacum L. cv. Ky-14
Nicotiana tabacumt0 - Treatment
- solution Mo concentratione0
- Outcome
- Molybdenum concentratione0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Molybdenum concentration in all plant parts increased with increasing solution Mo concentration.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Sulfate reduced molybdenum concentration similarly across plant parts.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- Sulfatee0
- Outcome
- concentration of Moe0
- Direction
- reducede0
- Qualifier
- essentially equal in all plant partse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sulfate drastically reduced the concentration of Mo, and the inhibition was essentially equal in all plant parts.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
The first sulfate increment produced the greatest molybdenum reduction; further additions had little effect.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- first increment of SO 4 2− (0.05 meq/l)e0
- Outcome
- Moe0
- Direction
- Greatest reductione0
- Comparator
- further additions of SO 4 2−e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Greatest reduction of Mo occurred with the first increment of SO 4 2− (0.05 meq/l), with little effects from further additions of SO 4 2− .”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Sulfate inhibition of molybdenum content was attributed chiefly to absorption and partly to root-to-leaf translocation.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- SO 4 2−e0
- Outcome
- Mo contente0
- Qualifier
- absorption processe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The data suggest that the inhibitory effects of SO 4 2− on Mo content occur primarily during the absorption process, with some antagonistic mechanism involved during translocation from roots to leaves.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Molybdenum did not inhibit sulfur accumulation.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- Molybdenume0
- Outcome
- S accumulatione0
- Direction
- not inhibitorye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Molybdenum was not inhibitory to S accumulation.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Leaves had greater molybdenum and sulfur content than other plant parts.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Organ / stage
- leavese0
- Outcome
- Contents of Mo and Se0
- Direction
- greatere0
- Comparator
- any other plant parte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Contents of Mo and S in leaves were greater than in any other plant part.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Nitrate reductase activity generally increased from lower to upper leaves.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Organ / stage
- bottom to top leavese0
- Outcome
- NR activitye0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“NR activity generally increased from bottom to top leaves.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
About 60% of plant nitrate reductase occurred in leaves.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Organ / stage
- leavese0
- Outcome
- NR in the plante0
- Value
- 60%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“About 60% of the NR in the plant occurred in the leaves.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
The newest open leaf and two or three leaves below it were suggested for maximum nitrate reductase sampling.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Organ / stage
- recent, completely open leafe0
- Outcome
- sampled for maximum NR activitye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the recent, completely open leaf (7–9 in. long) and the second and third leaves below it could be sampled for maximum NR activity”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Sulfate nutrition increased nitrate reductase activity through increased synthesis.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- Sulfate nutritione0
- Outcome
- NR activitye0
- Direction
- increasede0
- Qualifier
- increased NR synthesise0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sulfate nutrition increased NR activity, as a result of increased NR synthesis”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Molybdenum nutrition had no effect on nitrate reductase activity.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- Mo nutritione0
- Outcome
- NRe0
- Direction
- without effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Mo nutrition was without effect on NR in these experiments.”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Sulfate did not affect nitrate content.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- SO 4 2−e0
- Outcome
- NO 3 − contente0
- Direction
- not affectede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The NO 3 − content was not affected by SO 4 2−”
t0“Nicotiana tabacum L. cv. Ky-14”
Claim · model-written summary
Nitrate content increased without molybdenum.
- Taxon
- Nicotiana tabacum L. cv. Ky-14Nicotiana tabacumt0
- Treatment
- absence of Moe0
- Outcome
- NO 3 −e0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“NO 3 − increased in the absence of Mo.”
t0“Nicotiana tabacum L. cv. Ky-14”
The same questions in other papers
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molybdenum atom · nutrient: content · Nicotiana tabacum (tobacco)Positive and negative results
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4 papers more in this group
See all 8 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.