Clonal sectors reveal that a specific meristematic domain is not utilized in the maize mutant narrow sheath

Dev Biol. 1997 Feb 1;182(1):52-66. doi: 10.1006/dbio.1996.8452.


The narrow leaf and shortened stem phenotypes of the maize mutant narrow sheath (ns) are postulated to result from the lack of founder cell initialization in a region of the meristem that gives rise to leaf and stem margins. To test this model, a lineage map of the maize meristem is presented which compares the development of leaf margins in the narrow leaf mutant, narrow sheath (ns), and wild-type sibling plants. X-irradiation of mature seeds produced aneuploid albino sectors in wild-type and ns mutant plants. Of particular interest are sectors occurring in more than one leaf, which reflect a meristematic albino cell lineage. Analyses of these sectors indicated that: (1) a region of the ns meristem does not contribute to the founder cell population of the incipient leaf; (2) the margins of ns mutant leaves are derived from a lateral region of the meristem different from those in wild-type siblings; (3) founder cells in wild-type, juvenile-staged vegetative meristems encircle the meristem to a greater extent than do founder cells in adult-staged meristems; and (4) meristematic leaf founder cells may be subdivided into specific lateral domains, such that the position of a sector on the meristem correlates with a particular cell lineage. These data support our model for ns gene function in a specific domain of the meristem.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Meristem / physiology
  • Meristem / ultrastructure
  • Microscopy, Electron, Scanning
  • Phenotype
  • Plant Leaves / physiology
  • Plant Leaves / ultrastructure
  • Species Specificity
  • Zea mays / anatomy & histology
  • Zea mays / genetics*