Preliminary assessment of potential biocontrollers of Iris pseudacorus l. in the invaded range

GERVAZONI, PAULA B.; FUENTES RODRÍGUEZ, D.; SOSA, A.; COETZEE, JULIE A.; BERTUCCI, SABRINA; KRAMARZ, DAHIANA; FRANCESCHINI, M. C.

Chillan

Simposio; V Simposio Chileno de Control Biológico; 2022

Instituto de Investigaciones Agropecuarias (Chile)

Iris pseudacorus L. (Iridaceae) (yellow iris) is an invasive alien species (IAS) native from Europe,North Africa, and West Asia. This species not only causes economic impacts by invading ruraland urban areas, but also produces a great damage to wetland’s native biodiversity in manycountries of the world. Currently, there is an international alliance between Argentina, SouthAfrica, Belgium and New Zealand, aimed at testing the feasibility of applying classical biologicalcontrol against this weed with the candidate Aphthohanonstriata, native from Europe.However, there are still no assessments of potential biocontrollers already associated with I.pseudacorus in the invaded range. We analyzed the biodiversity of insect assemblagesassociated with I. pseudacorus in Argentinian wetlands. Systematic and random sampling werecarried out in urban, rural, natural and artificial invaded wetlands, in the Pampean, Central andNorthwest regions of Argentina, taking into account aerial parts of plants and capsules. Aspreliminary results, 343 individuals corresponding to 11 orders were obtained, being the mostabundant Hemiptera, Diptera and Coleoptera. The most represented species of herbivorousinsects belonged to the families Aphididae, Pentatomidae and Curculionidae. Severalcoleopteran species were recorded feeding on seeds inside the capsules, among whichAraecerusfasciculatus was the most represented. These results indicate an absence of specieswith biocontrol potential for I. pseudacorus in the sampled sites. Although herbivorous insectswere recorded on the plant, many of them can be attributed to occasional visits due to their lowrepresentation. Regarding the most abundant species, they correspond to polyphagous species,and cannot be considered for weed biocontrol. These results emphasize the need to continuetesting the feasibility of applying classical biocontrol with candidates from the native range ofthe plant that demonstrate specificity for I. pseudacorus.