Development of the Inflorescences

  • Erik Vollbrecht
  • Robert J. Schmidt


The maize tassel and ear are complex structures that arise from a shared program of development involving a number of meristem identities and fates, yet emerge as distinct inflorescences that bear exclusively male and female flowers, respectively. Careful phenotypic and genetic studies of mutants that perturb meristem initiation, size, determinacy and identity or pathways of organogenesis such as sex determination, are elaborating the intricacies of these developmental programs by providing important insights into the underlying genes and gene interactions. Our understanding at the molecular level includes information from expression patterns of cloned genes coupled with knowledge of the gene products they encode and interact with, coalescing into molecular bases for the mechanisms underlying the formation of these remarkable structures. These studies show that some mechanisms are at least partially conserved with those elucidated in other model systems such as Arabidopsis, but many others are unique to the grasses. Permeating advances in our understanding of the maize inflorescence is a rich collection of mutants, some identified at the turn of the last century and new ones recorded in databases of productive EMS- and transposon-based screens, constituting a key genetic resource that will provide fertile ground for maize geneticists and developmental biologists for years to come.


Floral Organ Floral Meristem Polar Auxin Transport Axillary Meristem Inflorescence Meristem 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors wish to acknowledge contributions by colleagues and lab members (past and present) in the form of stimulating discussions, and toward images and figures appearing in this chapter. Special thanks to G. Chuck for Fig. 6a, D. Hall for work on Fig. 2g, h. We also acknowledge the generous support of the National Science Foundation and the U.S. Department of Agriculture CSREES.


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Authors and Affiliations

  • Erik Vollbrecht
  • Robert J. Schmidt

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