A suspicious thread in the garden
If in your garden you notice a thin thread that twists around the plants, do not ignore it. You may have in front of the cushion, one of the most insidious and underestimated plants. At first glance it may seem like a simple wire of grass or a fragile climbing. In reality, it is an extremely aggressive plant parasite.
Its drums are thin, branched, white, yellow or greenish in color. They attach themselves to nearby plants because the cushion does not have chlorophyll. It does not produce energy alone, so it steals nourishment directly from the other plant species.
Once you insinuate itself, it begins to grow rapidly and intertwine with the guest plant. Within a short time, it can transform a healthy ejugal into an orange-yellowish tangle, almost similar to a vegetable spider web.
How to really recognize it
Cuscuta has no leaves and does not have a developed radical apparatus. He lives suspended among the stems of the other plants, supported exclusively by his “guests”. Small white, yellow or pink flowers appear on its thin branches. The fruits are capsules containing few seeds, but very resistant.
When its presence increases, it shapes real intricate tangles that surround the target plants. It is at that moment that the situation becomes serious: the struck plants begin to weaken, lose color, stop growing correctly and, in many cases, die.
The most popular species in Italy include European cusc into, Epithymum cusc into couscuta, Epilinum Cuscuta and pentagona cuscute. It is located both in tropical and temperate areas, grows from sea level to mountain areas. Colonizes cultivated fields, meadows, pastures, vegetable gardens and gardens. He mainly loves legumes and medical grass, but can adapt to many other plants.
It is not any plant: it is a complete parasite
Cuscuta works ruthlessly. During the initial phase of germination, it emits a root that provides it with energy for a few days. Immediately afterwards he desperately looks for a guest plant. If he finds it, he wraps around his stem and develops austers, tiny suction cups capable of piercing vegetable tissues and reaching the lymphatic vessels.
At that point, the original root dies. Cuscuta lives completely suspended, supported and nourished by the sap of the target plant. This is why it is called “vampire plant”, “vegetable mint” or “field leeches”.
A healthy plant becomes a constant source of energy for cuscuta, which can grow very quickly, even dozens of centimeters per day.
Cuscuta also steals the DNA
This plant is not satisfied with sucking the sap. Recent studies have shown that it also absorbs genes with a guest plant, integrating them into their genome.
An article published on Nature He revealed that the Cuscuta DNA contains numerous foreign genes. This occurs thanks to a phenomenon called horizontal gene transfer. It is a common process in bacteria, but rare in higher plants. It consists in the movement of genetic material between different organisms without going through sexual reproduction.
According to Professor Claude Depamphilis of Penn State University, cushion is an exceptional case: “In complex plants it is rare to see functional horizontal genetic transfers. In this case, not only the genes are absorbed, but the plant uses them actively”.
A successful evolutionary theft
Cuscuta does not accumulate these genes by chance. Reuse them to improve their biological skills. Some genes stolen are needed to develop more efficient defense systems, others to optimize the connection with the guest.
In total 108 gene sequences have been identified during its evolution. Many of these come from remote periods, a sign that cushion has been able to select and keep over time what was useful.
Scientists also suspect a possible reverse exchange: some genes may flow from the host to the guest. If confirmed, this would mean that between the two plants there is a sort of unilateral “genetic dialogue”, however dominated by the parasite.
The plant that spies on and steals flowering
Cuscuta has no leaves, therefore it cannot perceive light and environmental stimuli like other plants. Yet it blooms every year, in perfect synchrony with the guest. How do you do it?
A study published on Pnas From a team of the Max Planck Institute and the Chinese Academy of Sciences it has solved the mystery. The species analyzed, Cuscuta Australis, uses the guest plant not only to feed, but also to steal information.
In normal plants, flowering is regulated by a protein produced in the leaves, the flowering locus t (FT), which reports when the time has come to bloom. Cuscuta intercepts this protein through its austers, lets it migrate to her body and starts flowering at the same time as the guest.
If he flourished too late, he would risk not having enough resources; If it flourished too early, it would run out before time. Synchronating is its strategy to maximize survival.
A silent enemy in the fields
The presence of cuscute can become a serious agricultural problem. In the medical and legumes fields it can cause significant production drops. Once installed, eliminating it is not simple.
The seeds of the cushion resist in the ground for years, ready to germinate on the first occasion. Selective herbicides often are not enough. In many cases the infested plant must be physically eliminated, cutting and burning the residues to avoid the dispersion of the seeds.
A less known side: medicinal use
Despite its left fame, cuscute has been used for centuries in popular medicine. Some species have colagoghe, laxative and diuretic properties. In Asia, seeds are used in infusions to treat liver and kidney disorders.
Obviously, this does not cancel its parasitic nature, but shows how man has managed to benefit even from such an invasive plant.
Cuscuta represents one of the most fascinating and disturbing cases of the plant world. It has no roots, has no leaves, does not produce energy by itself. He lives sucking life, lymph and even DNA from the plants that infests.
His ability to synchron himself with the flowering of the guest and to exploit stolen genes makes it an extremely sophisticated parasite. Those who consider it “only a herba” makes a mistake.
If you individuals in your garden or in the fields, act immediately. Cut, Burn and remove any residue. A small thread today can become a difficult infestation to check tomorrow.
