The Journal of Heredity 1997:88(6):545-549
© 1997 The American Genetic Association 88:545-549
other |
Differences in Pollen-Tube Growth Rate and Reproductive Isolation Between Louisiana Irises
Department of Genetics, University of Georgia Athens, GA 30602
S. E Carney is now at the Department of Biology, Indiana University Bloomington, Indiana
Corresponding Editor: Kendall R. Lamkey
Abstract
A level of reproductive isolation is necessary for the process of genetic divergence. Such isolation also prevents the homogenization of species following secondary contact. This study is an investigation of the relative contribution of two prefertilization mechanisms, pollen-tube growth rate and pollen-tube attrition, to the reproductive isolation of Iris fulva and I. brevicaulis, two naturally hybridizing members of the Louisiana iris species complex. Flowers of each species were first pollinated with heterospecific pollen. After various time intervals, conspecific pollen was added. Analyses of the patterns of resulting progeny were used to infer whether relative pollen-tube growth rates act as a prefertilization isolating mechanism. In I. fulva the frequency of hybrid seeds increased with increasing pollination interval, suggesting that hybridization is limited by pollen-tube growth rates. Likewise, in I. brevicaulis hybrid seed production increased, but it was high regardless of the pollination interval. Thus it appears that relative pollen-tube growth rates limit interspecific reproduction in both species, but barriers are weaker in I. brevicaulis.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
M. A. Chapman, D. G. Forbes, and R. J. Abbott Pollen competition among two species of Senecio (Asteraceae) that form a hybrid zone on Mt. Etna, Sicily Am. J. Botany, April 1, 2005; 92(4): 730 - 735. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. T. Brock The potential for genetic assimilation of a native dandelion species, Taraxacum ceratophorum (Asteraceae), by the exotic congener T. officinale Am. J. Botany, May 1, 2004; 91(5): 656 - 663. [Abstract] [Full Text] [PDF] |
||||
