Carpobrotus edulis: what doesn?t kill it makes it stronger

RODRÍGUEZ J; NOVOA A; SOTES GJ; PAUCHARD A; CORDERO-RIVERA A; GONZÁLEZ L

Dublin

Congreso; 10th International Conference in Biological Invasions; 2018

Carpobrotus edulis is considered as oneof the most dangerous invasive species worldwide. It invades coastal habitats, suchas cliffs and sand-dunes, salt marshes and coastal scrub. However, it can alsobe found on roadsides and railway lines inland. At present, both generalist andspecialist herbivore species are known to feed on C. edulis in both its native and invaded ranges. Nevertheless, itis not known if C. edulis has adifferent response according to the type of herbivore that feeds on it. The aimof this study is to assess the performance response of C. edulis from different origins (native vs invaded) when it isbeing attacked by both generalist and specialist herbivores. Todo this, we collectedseedsofC. edulisinits native (SouthAfrica) and invaded (Chile and Spain) ranges, and both a generalist (Philaenus spumarius) herbivore native toEurope and a specialist (Pulvinariella mesembryanthemi)herbivore native to South Africa as herbivore treatment (collected in areasinvaded by C. edulis in NW Spain). Ina greenhouse experiment in Spain, we grew a total of 90 individuals of C. edulis (30 individuals per origin) for3 months, which were subsequently inoculated with the respective herbivorytreatments for another 3 months. Our results showed that C. edulis (independently of its origin) presentsan induced systemic resistance to herbivores, which was expressed by acompensatory growth response when exposed to the generalist herbivore. Incontrast, we found the specialist herbivore to cause severe damage to C. edulis, even death. Carpobrotus edulis individuals fromSouth Africa and Chile showed a higher resistance to the presence ofherbivores, compared to individuals from Spain. This suggests that the responseof C. edulis to both generalist andspecialist herbivores varies depending on its origin.