Seven new species of wild tobacco in the Nicotiana genus, all found in the Australian arid zone, have been described by scientists from the Royal Botanic Gardens, Kew, Curtin University and University of Vienna.
One of the species described, N. insecticida, was found to have sticky glands covering its surfaces and was able to capture and kill small insects such as gnats, aphids and fleas.
This is the first time that a wild tobacco species has been found to kill insects. When some seeds were collected by a truck stop in Northwest Coastal Highway in Australia, where the species was first found, and cultivated in London at Kew Gardens, on the other side of the world, the plants were still able to catch and kill insects. The species was then also found in other locations.
Although the species is able to capture and kill insects, it is not known whether the plant actually gains any nutritional benefits from the dead insects, and as yet, the species cannot be confirmed as carnivorous. Further research is planned to look into this.
The eight years of fieldwork formed part of a collaborative project between researchers from the UK, Australia and Austria, looking for wild tobacco species in all of Australia's states and territories except for Tasmania where these plants do not occur.
More recently described species:
“The arid parts of Australia, which is most of the continent, have been thought of as almost barren with limited plant diversity, but in recent years these poorly studied areas have yielded many new and unusual species,” says Professor Mark Chase, scientist at the Royal Botanic Gardens, Kew. “One of these, Nicotiana insecticida, demonstrates well the adage that ‘tobacco kills’, although in this case it is insects that become ensnared on its sundew-like glandular hairs and die.”
The other six species described recently include N. salina, growing along the salt lakes between Western Australia wheatbelt and the central region that is too dry for crop cultivation, and N. walpa, the name of which comes from the local Aboriginal language (Pitjantjatjara, the language of the Anangu people) for ‘wind’. This species only appears when there have been storms in the desert, and in between, the seeds remains in the soil. It has only ever been seen twice – in 1988 and again in 2016.
Several other Nicotiana species from the Australian arid zone still remain to be described.
Read the paper in Curtis's Botanical Magazine.
Main image: Nicotiana insecticida. © Maarten Christenhusz
