Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

A Cost of Restoration of Male Fertility in a Gynodioecious Species, Lobelia siphilitica

Maia F. Bailey
Evolution
Vol. 56, No. 11 (Nov., 2002), pp. 2178-2186
Stable URL: http://www.jstor.org/stable/3094660
Page Count: 9
  • Read Online (Free)
  • Download ($4.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
A Cost of Restoration of Male Fertility in a Gynodioecious Species, Lobelia siphilitica
Preview not available

Abstract

Models allowing the coexistence of females and hermaphrodites in gynodioecious populations assume a simple genetic system of sex determination, a seed fitness advantage of females (compensation), and a negative pleiotropic effect of nuclear sex-determining genes on fitness (cost of restoration). In Lobelia siphilitica, sex is determined by both mitochondrial genes causing cytoplasmic male sterility (CMS) and nuclear genes that restore fertility when present with specific CMS haplotypes (nuclear restorers). I tested for a cost of restoration in L. siphilitica by measuring restored hermaphrodites for five fitness components and estimating the number of nuclear restorers by crosses with females carrying CMS1 and CMS2. A cost of restoration appears as a significant negative coefficient (B) in the regression model explaining fitness. I found that hermaphrodites carrying more nuclear restorer genes for CMS2 (or restorer genes of greater effect) have lower pollen viability (B = -1.08, P = 0.001). This pollen viability cost of restoration in L. siphilitica supports the theoretical prediction that negative pleiotropic effects of restorers will exist in populations of gynodioecious species containing females. The existence of such a cost supports the view that gynodioecy can be a stable breeding system in nature.

Page Thumbnails

  • Thumbnail: Page 
2178
    2178
  • Thumbnail: Page 
2179
    2179
  • Thumbnail: Page 
2180
    2180
  • Thumbnail: Page 
2181
    2181
  • Thumbnail: Page 
2182
    2182
  • Thumbnail: Page 
2183
    2183
  • Thumbnail: Page 
2184
    2184
  • Thumbnail: Page 
2185
    2185
  • Thumbnail: Page 
2186
    2186