Are the Alien Species of Melastomataceae and Bombacoideae a Potential Risk for Brazilian Cerrado?

Abstract

The cultivation of species in urban areas for landscaping or consumption has increased in cities surrounded by Cerrado, putting in risk the local flora. Thus, the objective of this paper was to describe seed germination and seedling emergence of five urban cultivated species of Melastomataceae and Bombacoideae and compare them with Cerrado native species to evaluate if they offer any risk to local vegetation. The seeds were collected in the urban area of Uberlandia, within the Brazilian Cerrado. We calculated germination and emergence measurements and compared them to literature data. Seeds of Bombax ceiba and Pachira aquatica had a germination and emergence pattern similar to other Bombacoideae. Tibouchina pulchra and Tibouchina granulosa also had a similar pattern to other Melastomataceae, with low germinability. In contrast, seed germination of Heterotis rotundifolia, an invasive African species, was similar to Clidemia hirta, also known as invasive, including the higher spreading of germination through time, a common character of invasive plants. Seed germination of H. rotundifolia was more similar to Cerrado species with dormant seeds, showing high germinability and germination spread through time. These features added to its fast-growing due to its decumbent herbaceous habit that forms dense mats could offer risks to local species. Thus, it is being recommended that its populations be monitored.