Abstract
Plant hormones are a group of organic natural compounds that can influence physiological processes when present at low concentrations. Plant biologists frequently use exogenous hormone application to modify plant physiology or to rescue mutants with defects in hormone pathways. There are a number of methods for these treatments, depending on the plant species, organs and tissues used for application, release path, among others. Here, we describe a simple method used for hormone treatment in maize plants. At the vegetative stage, we show the application of Gibberellic acid (GA3) to wild type and dwarf1 (d1) mutants result in cell elongation (Evans et al., 1995). DWARF1 Encodes a Gibberellin 3-Oxidase enzyme (Chen et al., 2014), so the dwarf phenotype is rapidly recovered by GA3 application. In addition, wild type plants show rapid stem elongation in response to GA3 application. At the reproductive stage, we use our method to apply Jasmonic acid (JA) to a tasselseed2 (ts2) mutant tassel. TS2 suppresses carpels in the tassel and in lower florets in the ear and ts2 mutants can be rescued by exogenous JA application (DeLong et al., 1993). In addition to detailing the procedure for hormone treatments, we discuss potential issues and other aspects worth considering when performing these methods.
Keywords: Maize, Hormones, Vegetative, Reproductive, Development
Materials and Reagents
Equipment
Procedure
Data analysis
Qualitative analysis can be done by taking pictures over the time to record phenotype changes. Quantitative analysis is carried out by making graphs showing the height of the plants or other quantitative traits in at least three independent replicates. Statistical analysis can be done using the average and standard deviation of measurements for each point.
Notes
For details about planting and growing maize, refer to Hake and Lunde (2018).
Recipes
The following solutions for different hormone treatments in maize have been used (Yan et al., 2012; Rosa et al., 2017). Notes:
Acknowledgments
MJAJ was supported by UC-MEXUS CONACYT and by NSF IOS-1238202 at the Dr. Sarah Hake Lab and by NSF IOS-1652380 at the Dr. Madelaine Bartlett Lab, where this protocol was developed. Authors would like to thank Dr. Sarah Hake and Dr. Madelaine Bartlett for their continuing scientific support. Authors declare no conflict of interest regarding the implementation of this protocol.
References
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