FREQUENCY OF INDUCED CHLOROPHYLL MUTATIONS IN DIPLOID AND TETRAPLOID BARLEY
Bibliographic record
Abstract
EEDS of a variety of barley (Opal B) and of the corresponding S autotetraploid strain were irradiated in 1940.The immediate effects of this treatment have already been described (MUNTZING, 1941).In the tetraploid material the germination of the seeds and the vigour of the resulting plants were on an average much less decreased than in the corresponding diploids.Also as regards fertility the average decrease was less pronounced in the tetraploids than in the diploids.This differential behaviour was ascribed to the fact that in the autotetraploid line there are four quite homologous genomes instead of only two as in the diploid.Thanks to this gene and chromosome duplication deleterious changes occurring at a certain locus in one chromosome will in most cases be counterbalanced by a normal condition in the other homologous chromosomes.This view was further supported by observations of the X,generatioh, grown in 1941.In the first place the production of chlorophyll mutations is of interest.When observing the seedlings in the field a distinct difference was at once evident between the diploid and tetraploid material.In the tetraploid plots not a single typical chlorophyll mutant could be detected.In the diploid plots, on the contrary, there was a rather frequent occurrence of the usual categories of chlorophyll mutations, viz.albina, xantha, alboviridis, viridis and tigrina (cf.GUSTAFSSON, 1940).The data available may be summarised in the following table (Table 1).As is evident from the table, 75 chlorophyll mutants were present in the X,-generation of the diploids among a total of 5,558 plants observed.These values were obtained by summation of the figures corresponding to 5,000, 10,000 and 15,000 r.In the tetraploids, 2,365 plants belonged to the X,-progenies corresponding to the same intensities of irradiation (5,000--15,000 r ).All these 2,365 plants were apparently normal, or, at any rate, they did not represent the clear-cut mutant categories occurring in the diploid material.Thus, the com-
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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 | 0.001 | 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) | 0.002 | 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".