Biological control of Cryptostegia madagascariensis in Brazil
Cryptostegia madagascariensis (Apocynaceae) is a species of vine native to Madagascar. It is grown as a garden ornamental in a number of countries globally, and it is recorded as an invasive alien plant species in Australia, Brazil, the Caribbean, the USA (Florida and Hawaii) and South Africa. It is one of two species in the genus and the congener Cryptostegia grandiflora has been the target of a successful classical biological control programme in Australia. C. madagascariensis can have a negative impact in areas where it invades, impacting biodiversity and ecosystem services. In the native range, the rust fungus Maravalia cryptostegiae (Chaconiaceae) was assessed as a potential biological control agent for C. madagascariensis in Brazil. Surveys in Madagascar sourced 22 strains of the rust and all of the strains were assessed for their compatibility and virulence towards Brazilian biotypes of C. madagascariensis. Molecular analyses of plant populations from both the native and introduced range were conducted, to confirm the identity of the invasive species in Brazil and where in the native range the Brazilian population originated. The molecular biogeographic study shows that the population in Brazil is homogenous and closely related to a geographically isolated population of C. madagascariensis in northern Madagascar. A strain of the rust collected from this area in Madagascar has been found to be specific and damaging to Brazilian populations of C. madagascariensis.
Sources
Pollard KM, Kurose D, Tilling AE, Gaskin JF, Devlin PF, Evans HC, Seier MK (2026) Finding the best match – use of the rust fungus Maravalia cryptostegiae for control of Cryptostegia madagascariensis in Brazil. Biological Control, 215, https://doi.org/10.1016/j.biocontrol.2026.106004
Seier MK, Rapini A, Pollard KM, Barreto RW, Evans HC (2023) Tracing the origins and tracking the movements of invasive rubber vines (Cryptostegia spp., Apocynaceae). NeoBiota 89, 95–133. https://doi.org/10.3897/neobiota.89.109180