Maturation of the tracheary elements in the roots of <i>Pinus banksiana</i> and <i>Eucalyptus grandis</i>
Bibliographic record
Abstract
Tracheary elements of the xylem are responsible for the longitudinal (axial) transport of water and ions that have moved radially across the root. These vessel members and (or) tracheids mature some distance behind the root tip, and it is generally believed that this distance is directly related to root growth rate. To test this idea, the distances behind the root tip at which tracheary elements of pouch-grown Pinus banksiana Lamb. and Eucalyptus grandis W. Hill ex Maiden mature were examined. From each species, three root tip types (white, brown, and ectomycorrhizal short lateral) were assessed. Unlike previous studies of this topic, two methods of testing tracheary element maturity were employed concurrently. The first was anatomical and involved visualizing the deposition of lignin in the walls of the tracheids or vessel members. The second was functional and consisted of determining the capability of the tracheary elements to conduct a fluorescent, tracer dye. The distance behind the root tip at which the conductive xylem cells mature varied from 0.16 to 1.6 mm and was highly dependent on species and root type. No significant correlation was found between growth rate and proximity of tracheary element maturation to the tip for white roots. The presence of lignin in the tracheary element wall was not a reliable indicator of the cell's functional maturity.Key words: conductivity, development, roots, tracheary elements, xylem.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".