Abstract
Changes in the distribution of dry weight, and of zinc and copper, between root plus stem and the leaflets and petioles of the individual leaves of young plants of Trifolium subterraneum L. var. Bacchus Marsh grown in zinc-deficient culture solution, have been traced during a period of 3 weeks. These changes were compared with those which took place in control plants grown in a culture solution which was adequately supplied with zinc. In control plants the dry weight and zinc content of each leaf exceeded that of the previous one. The dry weights of the cotyledons, the primary leaf, and the first trifoliate leaf on these plants began to decrease slowly after reaching a maximum, but there was no decrease in the dry weights of the younger leaves during the period of observation. The zinc content of each leaf on the control plants began to decrease rapidly after it had reached a maximum. Maximum zinc content was reached before maximum dry weight. These changes in dry weight and zinc content led to a decreasing concentration of zinc in each leaf as it emerged and unfolded, and they were responsible for wide differences between the concentrations of zinc in the leaves present at any one time. Symptoms of zinc deficiency were recognizable 25 days after germination in the plants grown in zinc-deficient cultures; a distinctive chlorosis appeared in the second trifoliate leaf when the leaflets began to unfold. Development of the third leaf was retarded and that of the fourth arrested in the affected plants, but the dry weight of the whole plant continued to increase at almost the same rate as that of control plants for a week after the chlorosis was first observed. The reason for this was traced to an abnormal increase in the weight of each of the oldest leaves after the onset of zinc deficiency. Zinc was transported more rapidly out of the cotyledons and primary leaf of zinc-deficient plants than out of corresponding leaves of control plants. The amounts of zinc in the trifoliate leaves of zinc-deficient plants were much less than those in corresponding leaves of the controls: a decreasing concentration of zinc which was observed in the trifoliate leaves of zinc-deficient plants was brought about by increases in dry weight without any appreciable change taking place in the amounts of zinc present. The changes that were observed in the concentrations of zinc in individual leaves of zinc-deficient and normal plants indicated that zinc was present in the leaves in highest concentration before they emerged and unfolded. Radioautographs showing the distribution of 65Zn in young plants confirmed this. Copper was transported out of the cotyledons of control plants. It was also transported out of the primary and trifoliate leaves of these plants, but only after a period of accumulation. The leaves took longer to accumulate a maximum amount of copper than to accumulate a maximum amount of zinc. The onset of zinc deficiency did not have a marked effect on the concentration of copper in the leaves, because abnormal increases in the dry weights of the leaves were accompanied by corresponding accumulations of copper.
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Claims 17
Claim · model-written summary
In controls, successive leaves had higher dry weight and zinc content.
- Taxon
- Trifolium subterraneum
Trifolium subterraneumt0 - Outcome
- dry weight and zinc content of each leafe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In control plants the dry weight and zinc content of each leaf exceeded that of the previous one.”
t0“Trifolium subterraneum”
Claim · model-written summary
Older control leaves lost dry weight after their maximum whereas younger leaves did not.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- dry weights of the cotyledons, the primary leaf, and the first trifoliate leafe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The dry weights of the cotyledons, the primary leaf, and the first trifoliate leaf on these plants began to decrease slowly after reaching a maximum, but there was no decrease in the dry weights of the younger leaves during the period of observation.”
t0“Trifolium subterraneum”
Claim · model-written summary
Control leaf zinc content rapidly declined after its maximum.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- zinc content of each leafe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The zinc content of each leaf on the control plants began to decrease rapidly after it had reached a maximum.”
t0“Trifolium subterraneum”
Claim · model-written summary
Leaf zinc content peaked before leaf dry weight.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- Maximum zinc contente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maximum zinc content was reached before maximum dry weight.”
t0“Trifolium subterraneum”
Claim · model-written summary
Zinc concentration fell as each leaf emerged and unfolded, with wide differences among leaves.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- concentration of zinc in each leafe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“These changes in dry weight and zinc content led to a decreasing concentration of zinc in each leaf as it emerged and unfolded, and they were responsible for wide differences between the concentrations of zinc in the leaves present at any one time.”
t0“Trifolium subterraneum”
Claim · model-written summary
Zinc deficiency produced chlorosis in the second trifoliate leaf at 25 days after germination.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Organ / stage
- second trifoliate leafe0
- Outcome
- distinctive chlorosise0
- Value
- 25 days after germinatione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Symptoms of zinc deficiency were recognizable 25 days after germination in the plants grown in zinc-deficient cultures; a distinctive chlorosis appeared in the second trifoliate leaf when the leaflets began to unfold.”
t0“Trifolium subterraneum”
Claim · model-written summary
Zinc deficiency retarded third-leaf development.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- Development of the third leafe0
- Direction
- retardede0
- Comparator
- control plantse0
Not reportedTreatment
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Development of the third leaf was retarded and that of the fourth arrested in the affected plants, but the dry weight of the whole plant continued to increase at almost the same rate as that of control plants for a week after the chlorosis was first observed.”
t0“Trifolium subterraneum”
Claim · model-written summary
Zinc deficiency arrested fourth-leaf development.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- that of the fourth arrestede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Development of the third leaf was retarded and that of the fourth arrested in the affected plants, but the dry weight of the whole plant continued to increase at almost the same rate as that of control plants for a week after the chlorosis was first observed.”
t0“Trifolium subterraneum”
Claim · model-written summary
Whole-plant dry weight increased at almost the control rate for a week after chlorosis.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- dry weight of the whole plante0
- Direction
- increasee0
- Comparator
- control plantse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the dry weight of the whole plant continued to increase at almost the same rate as that of control plants for a week after the chlorosis was first observed.”
t0“Trifolium subterraneum”
Claim · model-written summary
Oldest leaves gained abnormal weight after zinc deficiency began.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- weight of each of the oldest leavese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“an abnormal increase in the weight of each of the oldest leaves after the onset of zinc deficiency.”
t0“Trifolium subterraneum”
Claim · model-written summary
Zinc moved more rapidly out of cotyledons and primary leaves in deficient plants.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- Zinc was transportede0
- Direction
- more rapidlye0
- Comparator
- control plantse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Zinc was transported more rapidly out of the cotyledons and primary leaf of zinc-deficient plants than out of corresponding leaves of control plants.”
t0“Trifolium subterraneum”
Claim · model-written summary
Deficient trifoliate leaves held much less zinc than controls.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- amounts of zinc in the trifoliate leavese0
- Direction
- much lesse0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The amounts of zinc in the trifoliate leaves of zinc-deficient plants were much less than those in corresponding leaves of the controls”
t0“Trifolium subterraneum”
Claim · model-written summary
Zinc concentration declined in deficient trifoliate leaves because dry weight grew while zinc amount scarcely changed.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- decreasing concentration of zince0
- Qualifier
- increases in dry weighte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a decreasing concentration of zinc which was observed in the trifoliate leaves of zinc-deficient plants was brought about by increases in dry weight without any appreciable change taking place in the amounts of zinc present.”
t0“Trifolium subterraneum”
Claim · model-written summary
Leaf zinc concentration was highest before leaf emergence and unfolding.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- highest concentratione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“zinc was present in the leaves in highest concentration before they emerged and unfolded. Radioautographs showing the distribution of 65Zn in young plants confirmed this.”
t0“Trifolium subterraneum”
Claim · model-written summary
Copper moved out of control cotyledons and later out of primary and trifoliate leaves.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- Copper was transported out of the cotyledonse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Copper was transported out of the cotyledons of control plants. It was also transported out of the primary and trifoliate leaves of these plants, but only after a period of accumulation.”
t0“Trifolium subterraneum”
Claim · model-written summary
Leaves took longer to reach maximum copper amount than maximum zinc amount.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- maximum amount of coppere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The leaves took longer to accumulate a maximum amount of copper than to accumulate a maximum amount of zinc.”
t0“Trifolium subterraneum”
Claim · model-written summary
Zinc deficiency did not markedly change leaf copper concentration because copper accumulation tracked weight gain.
- Taxon
- Trifolium subterraneumTrifolium subterraneumt0
- Outcome
- concentration of copper in the leavese0
- Qualifier
- corresponding accumulations of coppere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The onset of zinc deficiency did not have a marked effect on the concentration of copper in the leaves, because abnormal increases in the dry weights of the leaves were accompanied by corresponding accumulations of copper.”
t0“Trifolium subterraneum”