Heliotropium amplexicaule (blue heliotrope)

Heliotropium amplexicaule (blue heliotrope)

The blue heliotrope is an important weed of South American origin considered invasive in Africa, Europe, Oceania, and Chile. In Australia it is considered one of the worst pasture weeds because it displaces desirable pastures and is toxic to livestock. FuEDEI researchers are working on testing a species of Argentine flea beetle, Longitarsus sp., on native Australian plants, to evaluate its potential as a biological control agent.

Blue heliotrope (Heliotropium amplexicaule) is a perennial forb native to South America. Its attractive inflorescence and resilience make it an attractive ornamental, which caused its introduction in various parts of the world. This led to biological invasions in environments in which the absence of specialized natural enemies allows it to behave as an invasive weed of pastures and grasslands, particularly in Australia. In these environments it develops in such a way that it displaces desirable forage plants, threatening the productivity of pastures and the health of livestock due to its toxic pyrrolizidine alkaloids.

In 2024, FuEDEI researchers began a project to evaluate the potential of the alticine chrysomelid Longitarsus sp. (possibly a new species not yet described) as a biological control agent for Australia. To this end, the specificity – in terms of feeding, reproduction, and generational survival – of said beetle will be tested on several Australian plants. The work is carried out in the national quarantine, located on the premises of the INTA Castelar, and it is the first time that FuEDEI carries out quarantine work with plants brought from abroad.

Personnel in charge:
Marina Oleiro, Guillermo Cabrera Walsh

Andrew McConnachie, Assad Shabbir, Muhammad Nawaz – Weed Research Unit, NSW Department of Primary Industries