By organism › Green plants › Ephedraceae › Ephedra nevadensis

Intervention effectobservedoriginal resultnegativemeasured

Claim · model-written summary

High CO2 reduced leaf to sapwood area ratio by 33% in field grown Ephedra nevadensis.

Taxon: Ephedra nevadensisEphedra nevadensise0
Treatment: high CO 2e0
Outcome: ratio of transpirational surface area to sapwood area (LSR)e0
Direction: reductionse0
Value: 33%e0
Setting: field‐growne0

Not reportedComparator

Verbatim

e0
“field‐grown Ephedra nevadensis and glasshouse‐grown Larrea tridentata responded to high CO 2 with reductions in the ratio of transpirational surface area to sapwood area (LSR) of 33% and 60%, respectively”
✓ located verbatim in the source · abstract, characters 873–1077

Title

Water use of two Mojave Desert shrubs under elevated CO₂

D. E. Pataki; T. E. Huxman; D. N. Jordan; et al. Global Change Biology 2000. doi:10.1046/j.1365-2486.2000.00360.x

Other claims from this paper (5)

Intervention effect High CO2 reduced leaf to sapwood area ratio by 60% in glasshouse grown Larrea tridentata.
Intervention effect Leaf specific hydraulic conductivity increased under elevated CO2.
Intervention effect Stomatal conductance stayed constant or increased under elevated CO2 in the responsive shrubs.
Intervention effect Field grown Larrea did not show reduced leaf to sapwood area ratio under high CO2.
Intervention effect High CO2 reduced stomatal conductance in field grown Larrea only with unusually high soil moisture.

Observationobservedoriginal resultmeasured

Claim · model-written summary

Ephedra nevadensis seedlings emerged from February through June.

Taxon: Ephedra nevadensisEphedra nevadensise0
Outcome: emerged over an extended period from February through Junee0

Verbatim

e0
“Seedlings of Ephedra nevadensis and of the grasses Agropyron and Pseudoroegneria spicata emerged over an extended period from February through June.”
✓ located verbatim in the source · abstract, characters 797–945

Title

Temporal Patterns of Seedling Emergence and Early Survival of Great Basin Perennial Plant Species

L. David Humphrey; Eugene W. Schupp ScholarsArchive (Brigham Young University) 1999

Other claims from this paper (16)

Observation Four seasonal emergence patterns were evident among the seeded species.
Observation Most shrubs except Ephedra nevadensis emerged from February to April.
Observation Agropyron seedlings emerged from February through June.
Observation Pseudoroegneria spicata seedlings emerged from February through June.
Observation Most other grasses and two forbs began emerging in April and continued into June.
Observation Pleuraphis jamesii emergence began in May.
Observation None of the emerged chenopod shrub seedlings survived.
Observation Survival of two Chrysothamnus species was low.
Observation Pseudoroegneria and Agropyron had the most surviving seedlings at the moister site.
Association Agropyron survival was more depressed at the drier 1994 site.
Association Native Elymus survival was not more depressed at the drier 1994 site.
Association Stipa, Oryzopsis hymenoides and Pleuraphis survived at least as well at the drier site.
Association Ephedra survived at least as well at the drier site.
Intervention effect Burning greatly reduced Bromus at the 1995 site.
Intervention effect In 1995, burning increased survival of all species except Oryzopsis and Ephedra.
Observation Stipa, Oryzopsis and Pleuraphis had low emergence but consistently high survival.

Observationobservedoriginal resultmeasured

Claim · model-written summary

Following entry of a single binucleate sperm cell into the egg cell, one sperm nucleus migrates to fuse with the egg nucleus in Ephedra nevadensis.

Taxon: Ephedra nevadensisEphedra nevadensise1
Organ / stage: egg celle1
Outcome: one sperm nucleus migrates in a chalazal directione1

Verbatim

e1
“In Ephedra nevadensis, following entry of a single binucleate sperm cell into the egg cell, one sperm nucleus migrates in a chalazal direction to fuse with the egg nucleus”
✓ located verbatim in the source · abstract, characters 268–439

Title

Sexual Reproduction in Ephedra nevadensis (Ephedraceae): Further Evidence of Double Fertilization in a Nonflowering Seed Plant

William E. Friedman American Journal of Botany 1990. doi:10.2307/2444491

Other claims from this paper (5)

Observationobservedoriginal resultmeasured

Claim · model-written summary

The ventral canal nucleus regularly migrates to a central position in the egg cytoplasm and fuses with a second sperm nucleus.

Taxon: Ephedra nevadensisEphedra nevadensist0
Organ / stage: egg celle2
Outcome: the ventral canal nucleus regularly migratese2

Verbatim

t0
“Sexual Reproduction in Ephedra nevadensis”
✓ located verbatim in the source · title, characters 0–41

e2
“Contemporaneous with this first fertilization event, the ventral canal nucleus regularly migrates from its initially apical position within the egg cell to a more central position within the egg cytoplasm, where it fuses with a second sperm nucleus”
✓ located verbatim in the source · abstract, characters 441–689

Title

Sexual Reproduction in Ephedra nevadensis (Ephedraceae): Further Evidence of Double Fertilization in a Nonflowering Seed Plant

William E. Friedman American Journal of Botany 1990. doi:10.2307/2444491

Other claims from this paper (5)

Observationobservedoriginal resultmeasured

Claim · model-written summary

Occasional supernumerary nuclei within the egg cell can be ruled out as participating in the second fertilization event.

Taxon: Ephedra nevadensisEphedra nevadensist0
Organ / stage: egg celle3
Outcome: participating in the second fertilization evente3
Qualifier: can be ruled oute3

Verbatim

t0
“Sexual Reproduction in Ephedra nevadensis”
✓ located verbatim in the source · title, characters 0–41

e3
“occasional supernumerary nuclei within the egg cell (derived by migration through pores in the cell walls between jacket cells and the central cell or egg cell) can be ruled out as participating in the second fertilization event”
✓ located verbatim in the source · abstract, characters 748–976

Title

Sexual Reproduction in Ephedra nevadensis (Ephedraceae): Further Evidence of Double Fertilization in a Nonflowering Seed Plant

William E. Friedman American Journal of Botany 1990. doi:10.2307/2444491

Other claims from this paper (5)

Mechanismhypothesisoriginal resultbasis n/a

Claim · model-written summary

Comparative evidence is consistent with double fertilization having arisen in a common ancestor of the Gnetales and angiosperms.

Taxon: Ephedra nevadensisEphedra nevadensist0
Outcome: double fertilization arose in a common ancestor of the Gnetales and angiospermse6
Qualifier: comparative evidence is consistent with the hypothesise6

Verbatim

t0
“Sexual Reproduction in Ephedra nevadensis”
✓ located verbatim in the source · title, characters 0–41

e6
“comparative evidence is consistent with the hypothesis that double fertilization arose in a common ancestor of the Gnetales and angiosperms”
✓ located verbatim in the source · abstract, characters 1916–2055

Title

Sexual Reproduction in Ephedra nevadensis (Ephedraceae): Further Evidence of Double Fertilization in a Nonflowering Seed Plant

William E. Friedman American Journal of Botany 1990. doi:10.2307/2444491

Other claims from this paper (5)

Observationobservedoriginal resultmeasured

Claim · model-written summary

One sperm nucleus fuses with the egg nucleus after a binucleate sperm cell enters the egg cell.

Taxon: Ephedra nevadensisEphedra nevadensise0
Organ / stage: egg celle0
Outcome: one sperm nucleus migrates in a chalazal direction to fuse with the egg nucleuse0

Not reportedDirection

Verbatim

e0
“In Ephedra nevadensis, following entry of a single binucleate sperm cell into the egg cell, one sperm nucleus migrates in a chalazal direction to fuse with the egg nucleus.”
✓ located verbatim in the source · abstract, characters 268–440

Title

SEXUAL REPRODUCTION IN EPHEDRA NEVADENSIS (EPHEDRACEAE): FURTHER EVIDENCE OF DOUBLE FERTILIZATION IN A NONFLOWERING SEED PLANT

William E. Friedman American Journal of Botany 1990. doi:10.1002/j.1537-2197.1990.tb11399.x

Other claims from this paper (3)

Observationobservedoriginal resultmeasured

Claim · model-written summary

The ventral canal nucleus moves into the central egg cytoplasm and fuses with the second sperm nucleus.

Taxon: EPHEDRA NEVADENSISEphedra nevadensist0
Organ / stage: egg celle0
Outcome: fuses with a second sperm nucleuse0

Not reportedDirection

Verbatim

t0
“EPHEDRA NEVADENSIS”
✓ located verbatim in the source · title, characters 23–41

e0
“the ventral canal nucleus regularly migrates from its initially apical position within the egg cell to a more central position within the egg cytoplasm, where it fuses with a second sperm nucleus”
✓ located verbatim in the source · abstract, characters 494–689

Title

SEXUAL REPRODUCTION IN EPHEDRA NEVADENSIS (EPHEDRACEAE): FURTHER EVIDENCE OF DOUBLE FERTILIZATION IN A NONFLOWERING SEED PLANT

William E. Friedman American Journal of Botany 1990. doi:10.1002/j.1537-2197.1990.tb11399.x

Other claims from this paper (3)

Observationobservedoriginal resultmeasured

Claim · model-written summary

Supernumerary egg-cell nuclei were excluded as participants in the second fertilization event.

Taxon: EPHEDRA NEVADENSISEphedra nevadensist0
Outcome: supernumerary nuclei within the egg celle0
Qualifier: can be ruled out as participating in the second fertilization evente0

Not reportedDirection

Verbatim

t0
“EPHEDRA NEVADENSIS”
✓ located verbatim in the source · title, characters 23–41

e0
“occasional supernumerary nuclei within the egg cell (derived by migration through pores in the cell walls between jacket cells and the central cell or egg cell) can be ruled out as participating in the second fertilization event”
✓ located verbatim in the source · abstract, characters 748–976

Title

SEXUAL REPRODUCTION IN EPHEDRA NEVADENSIS (EPHEDRACEAE): FURTHER EVIDENCE OF DOUBLE FERTILIZATION IN A NONFLOWERING SEED PLANT

William E. Friedman American Journal of Botany 1990. doi:10.1002/j.1537-2197.1990.tb11399.x

Other claims from this paper (3)

Observationauthor interpretationoriginal resultmeasured

Claim · model-written summary

Comparative evidence is consistent with double fertilization arising in a common ancestor of Gnetales and angiosperms.

Taxon: EPHEDRA NEVADENSISEphedra nevadensist0
Outcome: double fertilization arose in a common ancestor of the Gnetales and angiospermse0

Not reportedDirection

Verbatim

t0
“EPHEDRA NEVADENSIS”
✓ located verbatim in the source · title, characters 23–41

e0
“comparative evidence is consistent with the hypothesis that double fertilization arose in a common ancestor of the Gnetales and angiosperms”
✓ located verbatim in the source · abstract, characters 1916–2055

Title

SEXUAL REPRODUCTION IN EPHEDRA NEVADENSIS (EPHEDRACEAE): FURTHER EVIDENCE OF DOUBLE FERTILIZATION IN A NONFLOWERING SEED PLANT

William E. Friedman American Journal of Botany 1990. doi:10.1002/j.1537-2197.1990.tb11399.x

Other claims from this paper (3)

Ephedra nevadensis 22 claims

22 claims