The assessment of reproductive traits that promote invasiveness in Canna cultivars located in Howick and Pietermaritzburg
Sibiya, M.S.1,2, Nänni I. 2, Johnson S.D.1
1School of Life Sciences, University of KwaZulu-Natal; 2Invasive Species Programme, SANBI
Biological invasions, particularly invasions by invasive alien plants, are a major threat to the biodiversity and economy of South Africa and globally. Plant invasions cost South Africa approximately R6.5 billion per year to control. As a consequence, investigating invasive traits in plants can prove valuable in developing control protocols. Canna is a genus that is known to be invasive in southern Africa. However, there is little data on the invasion biology or pollination biology of Canna. This study aims at determining the reproductive traits that promote invasiveness in Canna cultivars growing in Pietermaritzburg and Howick. The reproductive traits of Canna cultivars will be assessed through breeding systems experiments and vegetative reproduction will be assessed through excavating seedlings to check root connections between parent and offspring plants. The working hypothesis of this study, based on the observation that seed set is high but birds and honeybees feed on nectar from holes pierced in the side of the corolla, is that the Canna cultivars in Pietermaritzburg are self-compatible and can self-pollinate because of the close proximity of the pollen and stigma. An alternative hypothesis is that the plants are pollinated by honeybees that collect pollen from the pollen presenters early in the morning. The findings of this study are to form a B.Sc. Honours thesis and will be submitted to an international journal for publication.