Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems

Gynodioecy, sexual dimorphism and erratic fruiting in Corynocarpus laevigatus (Corynocarpaceae)

P. J. Garnock-Jones A C , R. E. Brockie A and R. G. FitzJohn A B
+ Author Affiliations
- Author Affiliations

A Centre for Biodiversity and Restoration Ecology, School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand.

B Landcare Research, PO Box 40, Lincoln 7640, Canterbury, New Zealand.

C Corresponding author. Email:

Australian Journal of Botany 55(8) 803-808
Submitted: 27 March 2007  Accepted: 27 August 2007   Published: 14 December 2007


The New Zealand karaka tree, Corynocarpus laevigatus J.R. & G.Forst., is shown to be gynodioecious. Flowers on female plants have large but empty anthers and many set fruit. Flowers on male plants produce pollen and each has a fully developed ovule. On most male plants, a low proportion of flowers set fruit. Inflorescences and flowers on male and female trees are similar in overall appearance, except that the flower parts on males are larger and flowers open more widely. Even the gynoecia on male plants are larger in most respects. We also report that although trees retain their gender, their intensity of fruiting varies from year to year. Some observations indicate that other species of Corynocarpus in Australia and the south-western Pacific might also be gender dimorphic.


Sabrina Malcolm and Linda Sorensen assisted with recording observations. Bill Malcolm provided close-up photographs of flowers for Fig. 2 and Ewen Cameron provided a photocopy of an article. PGJ and RGF thank the Science Faculty at Victoria University for a summer research grant. We thank two anonymous referees for helpful comments on the manuscript.


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