Claim · model-written summary
Both clones had similar predawn leaf water potentials.
- Taxon
- Populus trichocarpa x P. deltoides
Populus trichocarpae0 - Outcome
- predawn leaf water potentialse1
- Direction
- no_changeinferrede1
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleTreatmentComparatorSettingValueQualifier
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Populus trichocarpa x P. deltoides (TD)”
e1“Although both clones exhibited similar predawn leaf water potentials”
Title
Drought resistance of two hybrid Populus clones grown in a large-scale plantation
T. J. Tschaplinski; G. A. Tuskan; G. M. Gebre; et al. Tree Physiology 1998. doi:10.1093/treephys/18.10.653
Other claims from this paper (19)
- Observation Clone TD stem volume was 40-146% larger than Clone DN by the end of the second growing season.
- Association Stem volume growth was independent of irrigation above 46 cm year(-1) in both clones.
- Association During the third growing season, stem volume growth of both clones was limited by the 46- and 76-cm irrigation treatments.
- Intervention effect By the end of the third growing season, trees at 46-cm irrigation were only half the size of trees at 137-cm irrigation.
- Observation The irrigation treatment differences in stem volume were maintained through the fifth growing season.
- Observation At the end of the third growing season (1994), Clone TD stem volumes at 76- and 137-cm irrigation were larger than Clone DN.
- Observation Clonal differences gradually decreased in subsequent years.
- Observation Clonal differences were not detectable after 5 years.
- Observation Stem volume relative growth rate of Clone DN was greater than that of Clone TD in all treatments.
- Observation Clone DN typically maintained higher midday leaf water potentials.
- Mechanism Higher midday leaf water potential in Clone DN suggests better stomatal control of water loss.
- Observation Clonal and treatment differences in osmotic potential at full turgor were minimal and did not explain the clonal differences in drought resistance.
- Intervention effect Root density and root density to stem volume ratio increased more in response to moderate drought in Clone DN than in Clone TD.
- Observation Moderate drought resulted in enhanced drought resistance in the poplar clones.
- Observation Moderate drought increased the capacity of the poplar clones to withdraw water from the soil.
- Mechanism The greater drought resistance of Clone DN was attributed to a more favourable water balance from stomatal regulation and greater root carbon allocation early in drought.
- Observation Clone DN growing at 46-cm irrigation had a low root density to stem volume ratio.
- Observation Root and shoot growth were constrained by severe drought.
- Mechanism Severe water limitation may have restricted the preferential allocation of carbon to belowground tissues.