By Paola Ugoletti, Darren Reidy, Michael B. Jones and Jane C. Stout
|Impatiens glandulifera (the larger species) and I. balfourii.|
The anthropogenic movement of species can bring together species which would be naturally separated by geographical barriers. One potential consequence is cross-fertilization and hybridisation between closely related species, which could result in novel, more versatile offspring, which could become more invasive than the parents. In order for hybridisation to occur between non-native plant species, they must flower at the same time, and their reproductive systems must allow interspecific (cross-species) pollen transfer. In addition, animal-pollinated species require appropriate flower visitors who include both species in their diet and who switch between them during a single foraging bout, thus mediating interspecific pollen transfer. Moreover, interspecific pollen must be able to germinate on the stigma and grow a pollen tube through the style, fertilize the ovule and form a functional seed, and the seed must be able to germinate and grow into a new plant.