Biologists have discovered how tomato plants identify Cuscuta as a parasite. The plant has a protein in its cell walls that is identified as ‘foreign’ by a receptor in the tomato.
Their findings have been published in the journal Nature Communications.
Cuscuta spp., also known as dodder, is a parasitic vine which grafts to the host plant using special suckers to obtain water, minerals and carbohydrates.
The parasite also attacks and damages crops such as oilseed rape, sweetcorn, soy, flax or clover.
Although the infection generally goes undetected by the host, some species of tomato defend themselves by forming wooden tissue which prevents the suckers from penetrating the plant.
In earlier research, biologists at Friedrich–Alexander University Erlangen–Nürnberg (FAU) discovered that these tomatoes possess a special receptor, the Cuscuta receptor 1 (CuRe1), which triggers the defence mechanism. But until now it was unclear how the receptor recognises the danger posed by the dodder.
The FAU researchers, joined by researchers at the University of Tübingen, the University of Tromsø, the UC Davis and the Sainsbury Laboratory in Norwich, have now succeeded in answering this question: the dodder possesses a specific marker in its cellular wall, a glycine-rich protein (GRP). Using its receptor CuRe1, the tomato is able to recognise the molecular pattern of the GRP and identify the dodder as a pathogen, and triggers the immune reaction as a result.
The new findings concerning the molecular dialogue between the Cuscuta marker and the tomato receptor may help to increase the resistance of crop plants against parasitic plants.
Source: Friedrich–Alexander University Erlangen–Nürnberg