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Tropaeolum

life science Maturity 5-7 Next article →

The genus *Tropaeolum* consists of approximately 80 different species of flowering plants. These plants can be annuals or perennials. Most species are herbaceous, meaning they have soft stems rather than woody ones. They are native to South and Central America. Many species are highly valued in gardens for their bright colors. They are also known by the common name nasturtium. This name comes from an oil they produce. This oil smells and tastes similar to watercress, which is known as *Nasturtium officinale*.

Tropaeolum tricolor 236431369
Tropaeolum tricolor 236431369

Physically, these plants have very distinct features. Their leaves are often peltate, which means they are shaped like a shield. The leaf stalk, or petiole, attaches to the center of the leaf rather than the edge. These petioles can be quite long. In some species, the stalks twine around other plants to provide support. The flowers are bisexual, meaning they contain both male and female reproductive parts. Each flower has five petals and five sepals. One of the sepals is modified into a long, funnel-shaped nectar spur. This spur sits at the back of the flower to hold nectar.

Tropaeolum peregrinum 31085425
Tropaeolum peregrinum 31085425

The reproductive parts of the flower are quite complex. The flowers are zygomorphic, which means they have bilateral symmetry. This means if you split them down the middle, the two sides would match. There are five clawed petals on each flower. The lower three petals look different from the upper two. The plant also has eight stamens arranged in two whorls of different lengths. The ovary is superior and contains three segments. It also features three stigmas located on a single style. After pollination, the plant produces a naked, nut-like fruit. This fruit contains three single seed segments.

Tropaeolum polyphyllum (3435166083)
Tropaeolum polyphyllum (3435166083)

Carl Linnaeus named this genus in his book, *Species Plantarum*. His choice of the name *Tropaeolum* was inspired by ancient Roman history. The Romans used trophy poles called *tropaeum* to display captured armor. Linnaeus felt the round leaves looked like shields. He also thought the bright flowers looked like blood-stained helmets. In the past, the genus included two other groups, *Magallana* and *Trophaeastrum*. *Magallana* was known for having winged fruit. *Trophaeastrum* was identified by its lack of nectar spurs. However, a molecular study in 2000 changed this classification. The study showed these groups were not distinct enough. Now, *Tropaeolaceae* is a monogeneric family, meaning it contains only this one genus.

Mashua, color amarillo con rayas negritas
Mashua, color amarillo con rayas negritas

There are many different types of *Tropaeolum* with unique traits. *T. majus* is the most common garden hybrid. It grows well in sunny areas and poor soil. In contrast, *T. polyphyllum* is a very hardy perennial from Chile. It grows in the Andes mountains at elevations up to 3,300 meters. Its underground rhizomes allow it to survive harsh winters. Another notable species is *T. tuberosum*, known as Mashua. This plant has been cultivated since before the Inca civilization. It produces edible tubers that are a major food source in the Andes. These tubers can produce crops of 30 tonnes per hectare at elevations above 1,000 meters.

Tropaeolum peregrinum 31085425
Tropaeolum peregrinum 31085425

Many parts of the *Tropaeolum* plant are useful to humans. The flowers and leaves of *T. majus* are edible. They have a peppery flavor. The flowers are very nutritious, containing about 130 mg of vitamin C per 100 g. They also contain up to 45 mg of lutein per 100 g. This is the highest amount of lutein found in any edible plant. Some people use the unripe seed pods as a condiment. They can be placed in vinegar to act like capers. In Germany, doctors prescribe a medicine called Angocin Anti-Infekt N. This herbal antibiotic is made from nasturtium and horseradish root.

Beyond food and medicine, these plants play roles in ecology. Gardeners often use them as companion plants. They can be used for biological pest control. Some varieties act as a trap crop to attract pests away from other plants. Others may help by attracting predatory insects. This shows how a single genus can connect to many different fields. It connects to human nutrition, ancient history, and modern medicine. Whether as a mountain survivor or a garden flower, *Tropaeolum* is a versatile group of plants.

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🖼️ Images & Media (5)
File:Tropaeolum peregrinum 31085425.jpg
Tropaeolum peregrinum 31085425.jpg
File:Tropaeolum polyphyllum (3435166083).jpg
Tropaeolum polyphyllum (3435166083).jpg
File:Tropaeolum tricolor 236431369.jpg
Tropaeolum tricolor 236431369.jpg
File:P7024519ナスタチウムサラダ.jpg
P7024519ナスタチウムサラダ.jpg
File:Mashua, color amarillo con rayas negritas.jpg
Mashua, color amarillo con rayas negritas.jpg
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