Traits underlying phosphorus use by the extremophyte Eutrema salsugineum
Bibliographic record
Abstract
The objective of this thesis was to study the response of Eutrema salsugineum (Yukon) plants to low phosphate (Pi) using seedlings and four- week-old plants grown on media formulated with variable phosphate (Pi). Seedlings showed similar root architecture whether grown with high Pi or without added Pi. Four-week-old plants grown with 0 or 2.5 mM Pi added to the soil had the same shoot biomass and relative growth rates. Confirmation that plants on low Pi were Pi-deficient despite lacking a Pi-starvation phenotype was provided by the increased expression of Pi-starvation-inducible genes (notably EsIPS2) in Pi-deprived plants. We also found that seedling roots on media lacking Pi did not acidify their rhizosphere nor did they show increased phosphatase secretion or phosphatase activity relative to roots of Pi-sufficient seedlings. In soil-grown plants, leaf P remobilization was slower during dark-induced senescence of Eutrema relative to similarly treated, Pi-starved Arabidopsis. Also related to metabolism, in vitro assays showed that the ratio of maximal PPi- and ATP- dependent phosphofructokinase activities approximated 1:1 and 2:1 for Eutrema leaf and root extracts, respectively, with no Pi-responsive changes found and, relative to Arabidopsis, Eutrema phosphoenolpyruvate carboxylase activities were high. The enzyme activities suggest Eutrema operates glycolytic by-passes under Pi sufficient and deficient conditions. Finally, transcripts for the transcription factors Phosphate Starvation Response 1 (PHR1) and WRKY75 were not Pi-starvation-inducible and were more abundant in Eutrema leaves than in leaves of Pi-deprived Arabidopsis. Global gene expression showed the leaf and root transcriptomes to be about 90% similar between 0 and 2.5 mM Pi- treated plants with 2,901 differentially expressed genes detected by DESeq2. In summary, Eutrema displays few Pi-starvation responsive traits whether those traits reflect changes at the level of gene expression or plant morphology, behaviour consistent with a specialist that is continuously primed for Pi starvation.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 |
| 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".