, Volume 57, Issue 2, pp 93–98

Quantitative studies of the mating system in two sympatric species of Ipomoea (Convolvulaceae)

  • R. A. Ennos

DOI: 10.1007/BF00131233

Cite this article as:
Ennos, R.A. Genetica (1981) 57: 93. doi:10.1007/BF00131233


The rates of outcrossing in sympatric populations of Ipomoea purpurea and I, hederacea were estimated (using electrophoretic markers) to be 70% and 7% respectively. The difference in outcrossing rate is not apparently due to differences in pollinator service received by the species, but is associated with differences in anther-stigma distance. In I. purpurea stigmas are generally exserted and there is much genetic variation for anther-stigma distance. Variation in this character has a significant effect on the ease with which selfpollination occurs. In contrast there is no variation for the character in the I. hederacea population, the anthers being invariably held at the same level as the stigma, an arrangement promoting self-pollination.

Copyright information

© Dr W. Junk Publishers 1981

Authors and Affiliations

  • R. A. Ennos
    • 1
  1. 1.Botany DepartmentUniversity of GeorgiaAthensUSA
  2. 2.Genetics DepartmentUniversity of NewcastleNewcastle upon TyneU.K.