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Abstract The developmental genetics of reproductive structure control in maize must consider both the staminate florets of the tassel and the pistillate florets of the ear synflorescences. Pistil abortion takes place in the tassel florets, and stamen arrest is affected in ear florets to give rise to the monoecious nature of maize. Gibberellin (GA) deficiency results in increased tillering, a dwarfed plant syndrome, and the retention of anthers in the ear florets of maize. Thesilkless1mutant results in suppression of silks in the ear. We demonstrate in this study that jasmonic acid (JA) and GA act independently and show additive phenotypes resulting in androeciousdwarf1;silkless1double mutant plants. The persistence of pistils in the tassel can be induced by multiple mechanisms, including JA deficiency, GA excess, genetic control of floral determinacy, and organ identity. Thesilkless1mutant can suppress both silks in the ear and the silks in the tassel of JA‐deficient and AP2 transcription factortasselseedmutants. We previously demonstrated that GA production was required for brassinosteroid (BR) deficiency to affect persistence of pistils in the tassel. We find that BR deficiency affects pistil persistence by an independent mechanism from thesilkless1mutant and JA pathway. Thesilkless1mutant did not prevent the formation of pistils in the tassel bynana plant2in double mutants. In addition, we demonstrate that there is more to thesilkless1mutant than just a suppression of pistil growth. We document novel phenotypes ofsilkless1mutants including weakly penetrant ear fasciation and anther persistence in the ear florets. Thus, the JA/AP2 mechanism of pistil retention in the tassel and silk growth in the ear are similarly sensitive to loss of the SILKLESS1 protein, while the BR/GA mechanism is not.
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Tasselyzer, a machine learning method to quantify maize anther exertion, based on PlantCV
SUMMARY Maize anthers emerge from male‐only florets, a process that involves complex genetic programming and is affected by environmental factors. Quantifying anther exertion provides a key indicator of male fertility; however, traditional manual scoring methods are often subjective and labor‐intensive. To address this limitation, we developedTasselyzer— an accessible, cost‐effective, and time‐saving method for quantifying maize anther exertion. This image‐based program uses the PlantCV platform to provide a quantitative assessment of anther exertion by capturing regional differences within the tassel based on the distinct color of anthers. We applied this method to 22 maize lines with six genotypes, showing high precision (F1score > 0.8). Furthermore, we demonstrate that customizing the parameters to assay a specific line is straightforward and practical for enhancing precision in additional genotypes. Tasselyzer is a valuable resource for maize research and breeding programs, enabling automated and efficient assessments of anther exertion.
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- Award ID(s):
- 2445607
- PAR ID:
- 10600751
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 121
- Issue:
- 4
- ISSN:
- 0960-7412
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/tpj.70014
