Identification and gene mapping of a panicle apical abortion mutant (<italic>paa1331</italic>) in rice
Bibliographic record
Abstract
Rice panicle is an important agronomic organ which influences yield, and its development directly determines the yield potential. Over the past decades, a large number of genes related to grain size and grain number have been cloned, but there are few reports on cloning and function characterization of genes related to panicle development. We aim to explore the genes that regulate the degeneration of rice spike, improve the regulation network of panicle development, and provide theoretical basis for molecular breeding. In this study, a stably inherited mutant showing perturbed development of panicle (panicle apical abortion 1331) was isolated from an ethyl methyl sulfate(EMS)mutagenized population of Yixiang 1B. Compared with the wild type, the mutant mainly showed a severe degeneration at the panicle tip (the affected florets account for as high as 53%), in addition to this, the plant height, tiller number and grain number were also affected. Observation on the development of panicle showed that the top spikelets of mutant paa1331 began to degrade during meiosis of the pollen mother cell, and the number of degenerated spikelets increased with the elongation of the young spike, distributing at the top of the first branch of the stem, while the number of degenerated spikelets showed a tendency to decrease gradually from top to bottom. Anatomical observations showed that the stamens of the mutant degenerated spikelets degenerated into linear, and the pulp was withered. The tissue section of mutant paa1331 and pollen staining assay showed that there were no pollen grains in the mutant anther, indicating that degeneration hindered the development of pollen; the vascular bundle of the mutant degenerated stem showed developmental defects, which may cause the transport of the material to be obstructed Trypan blue staining assay showed severe coloration of degraded spikelets on top of mutants, indicted that the panicle apical abortion was associated with programmed cell death. Hormone assay suggested that the IAA content of mutants was higher than that of wild type. Genetic analysis showed that mutant trait was controlled by a recessive gene. Combined the analysis of map-based cloning and De novo genome sequencing, we found one gene LOC_Os04g40720, of which the fourth exon has an A-to-G single base substitution, which resulted in a change from Asn to Asp. At present, this gene has not been reported to confer function in panicle development, thus we treated it as candidate gene.
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 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".