Informe de actividades

FRANCESCHINI, M. C.; DUFEK, M. I.; CABAÑA FADER, A.; MEDINA, W.; VALLE, N. G.; DAMBORSKY, M. P.

2022-06-01/2023-06-23

Biológica

Medio terrestre-Conservacion

Natural enemies of the invasive plant Harrisiamartinii (Cactaceae): Perspectives for biologicalcontrol from native and introduced areas. Sampling and data assessment were restricted to Corrientes and Chaco Provinces in this first stage of the project. Localization of Harrisia martinii plants was previously assessed by compiling data from 26 examined specimens in the botanical collections of the Botanical Institute of the Northeast. Almost of these specimens were collected before to 1990?s and many areas reported to have native vegetation with occurrence of H. martinii plants are currently strongly modified by anthropic effect, with scarce record of this plants at the location provided by the botanical collection. A morphological and taxonomical assessment was also made to distinguish H. martinii from its congeneric species, Harrisia bonplandii (Parm.) Britton & Rose, which grow in sympatry and is highly abundant at the Northeast of Argentina. A total of 29 H. martinii plants were sampled in Chaco and Corrientes provinces, along with their insects and other associated arthropods. Field observations were also carried out on the plants and their associated fauna.Damaged plants and cladodes were transported in plastic containers and placed under controlled light and temperature conditions for insect emergence. A total of 64 arthropods, mainly insects, were obtained from field samplings and laboratory rearing. This allowed us to detect presence of Dasiops bourquini whereas Nealcidion cereicola remained undetectable at the sampling sites. Regarding to the insect assemblages, preliminary taxonomical and functional analysis suggests that Diptera and Coleoptera were the most abundant insect taxa colonizing Harrisia plants. Saprophagous secondary colonizers of plant tissues were the most common, followed by Phytophagous feeding groups.