Natural enemies of the invasive plant Harrisia martinii (Caryophyllales: Cactaceae): Perspectives for biological control from native and introduced areas

FRANCESCHINI, M. CELESTE; DUFEK, MATIAS; KELK, LAUREN; MEDINA, WALTER; CABAÑA FADER, ANDREA; VALLE, NÉSTOR G.; DAMBORSKY, MIRYAM; TAYLOR, TAMARA

Puerto Iguazú, Misiones

Simposio; XVI International Symposium on Biological Control of Weeds; 2023

FuEDEI ? Buenos Aires

Poster presentation Session: 2-Target and agent selection “Natural enemies of the invasive plant Harrisia martinii (Caryophyllales: Cactaceae): Perspectives for biological control from native and introduced areas”Franceschini, Celeste1, Dufek, Matias1, Kelk Lauren2, Medina, Walter3, Cabaña Fader, Andrea1, Gerardo N. Valle3, Damborsky Miryam4 & Taylor, Tamara2 1 Laboratorio de Herbivoría y Control Biológico en Humedales (HeCoB), Centro de Ecología Aplicada del Litoral (CECOAL-CONICET-UNNE), Corrientes, Argentina.2 Queensland Department of Agriculture and Fisheries, GPO Box 267, Brisbane, Qld, Australia.3 Instituto de Botánica del Nordeste (IBONE-FCA-UNNE), Corrientes, Argentina.4 Biología de los Artrópodos, Departamento de Biología, Facultad de Ciencias Exactas y Naturales y Agrimensura (FACENA-UNNE), Corrientes, Argentina.E-mail address: Tamara.Taylor@daf.qld.gov.auHarrisia martinii is a terrestrial, much branched, erect to climbing cactus, with a native range of eastern Paraguay to north-east Argentina. In Australia, this species is invasive and can form dense infestations, choking out other pasture species and causing injuries to livestock. Harrisia cactus was introduced to the State of Queensland in Australia in the 1890s. Since then, it has been steadily increasing in density and distribution in Queensland and New South Wales. Management strategies for this cactus included chemical and mechanical means, as well biological control with agents imported from Argentina in the 1970s and 1990s, but to date the expected control has not been achieved. The aim of this research project is to further the knowledge of the interactions between Harrisia martinii and their natural enemies in the native range of Argentina, with a view to utilizing insects from Argentina as biological control agents in Australia, focusing on two biocontrol agent candidates: the fly Dasiops bourquini (Diptera: Loncheidae) and the beetle Nealcidion cereicola (Coleoptera: Cerambycidae). Localization and collection of insects and Harrisia plants will be done at the north of Argentina to produce and maintain a laboratory culture of the insects. Field observations will also be carried out to understand the environmental requirements and mating habits to rear these species. Once the methodology has been established, a small collection from the laboratory culture in Argentina will be exported to Australia. Methods and environmental conditions used in Argentina will be replicated at the QDAF quarantine laboratory facility in Australia to produce a new culture that will be used for host specificity testing on relevant and economically important species. This project is relevant because very little is known about the biology and ecology of D. bourquini and N. cereicola. Also, this research will further the knowledge of these two native insect species in Argentina, if insects establish in the introduced range, it will provide a desirable control of the cactus H. martini in Australia as well the exchange of a valuable field and laboratory experience to researchers, technical staff and students working on the project.