Researchers have discovered how the tomato plant protects itself from a common parasitic plant. The findings, just published in the journal Science, may lead to the development of better parasite prevention in other crops.
Dodder (Cuscuta reflexa) is a parasitic plant that causes severe damage to many types of crops. It requires a host to complete its lifecycle and wraps around the stems of other plant species. Once attached, dodder drains the host of water and nutrients using special organs called haustoria. This usually leads to the death of the host plant.
One type of tomato plant, Solanum lycopersicum, is resistant to dodder infections. After being attacked by the parasite, the tomato plant produces a tissue that blocks the haustoria. Unable to get water or nutrients, the dodder plant eventually dies. Other tomato cultivars and crops lack this defense.
A research team from the University of Tübingen’s Center for Plant Molecular Biology collaborated with scientists from the Sainsbury Laboratory in Norwich. They found and isolated a dodder-resistance gene in the S. lycopersicum cultivar. The gene codes for a cell surface receptor called CUSCUTA RECEPTOR 1, or CuRe1. The receptor recognizes a peptide factor found in dodder plants. When activated, the receptor triggers the tomato plant’s defense mechanisms. This is the first example of a plant having a defense against parasitic plant species. Normally, these types of defense mechanisms are used against microbial threats and insects.
The team transferred the CuRe1 receptors to other plant species. They found that the plants gained partial protection against dodder infections. This not only confirms the role of the receptor but also means we can potentially protect other crop species.
By understanding how plants defend themselves against parasites, we can develop better treatments and protections for vulnerable crops. The findings also provide new insight into how plants communicate and recognize each other on a cellular level.
Hegenauer et al. Detection of the plant parasite Cuscuta reflexa by a tomato cell surface receptor. Science (2016).