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Magadascars power plant

By Sereba Agiobu-Kemmer
03 September 2022   |   2:39 am
Rose periwinkle, Madagascar periwinkle (Catharanthus roseus Vinca roseus), by whatever name, is an evergreen shrub or herbaceous plant, sprawling along the ground or standing erect to 1m

Red cultivars

Rose periwinkle, Madagascar periwinkle (Catharanthus roseus Vinca roseus), by whatever name, is an evergreen shrub or herbaceous plant, sprawling along the ground or standing erect to 1m (three feet) in height, native and endemic to Madagascar in the tropical rain forest where its natural habitats was almost lost.

It was found growing on the sand and limestone soil in woodlands, forests, grasslands and disturbed areas. The herb is now a common ornamental plant found in gardens and homes across the world. It is naturalised in most tropical and subtropical regions, and escaped from cultivation, spreading in rocky outcrops and roadside dry Savannah, urban open places and cultivated areas.

Catharanthus roseus is a small upright shrub prized for its shiny green leaves and delicate-looking flower.

The glossy oval leaves are borne in opposite pairs on slender stems. One or more flowers are produced at the upper leaf axils. Each flower has a 1cm (0.4) long tube flattened out into a five-lanced shaped petal at the mouth, which is up to 4cm (1.5) wide.

Species flower colour is usually soft rose pink, or occasionally mauve or white. In the wild, it is an endangered plant; the main cause of decline is habitat destruction by slash and burn agriculture.

However, species plants are seldom seen in commerce, having been largely replaced by larger flowered cultivars, many of which are dwarf.

Rose periwinkle, Madagascar periwinkle or annual Vinca, an erect to spreading tender perennial in the Apocynaceae family (except for the spreading one) grows in a typical mound six to 18 inches (less frequently to 24 inches) tall and as wide. It produces attractive bushy foliage that is covered by often-profuse blooms.

The colourful flowers last through the year, in tropical conditions and from spring to the late autumn, in warm temperate climates. As an ornamental plant, it is appreciated for its hardiness in dry nutritionally deficient conditions, popular in subtropical gardens where the temperature never falls below 5°c to 7°c, and as a warm bedding plant in the temperate garden. Full sun and well-drained soil are preferred.

The renewed interest in Madagascar periwinkle is the result of success in plant breeding. Numerous cultivars have been selected, for variation in flower colour (pink, red, salmon, mauve, peach, reddish-orange and a combination of these colours (white with a red eye each etc.), and also for tolerance to cooler growing conditions in temperate regions.

Notable cultivars include award-winning “Polka Dot” a dwarf trailing type, ‘Albus’ (white flowers), Grape Cooler (rose pink, cool tolerant), Ocellatus group (various colours), ‘Peppermint cooler’ (white with red centre; cool tolerant). ‘Pink in Rose’ ‘Pretty in Pink, and ‘Parasol’ have flowers several times larger than any previous type. New cultivars are released regularly, increasing the popularity of the species. The glossy green foliage has few pest issues, but few can question its beauty in the landscape.

They can be used in a perennial border, as bedding plants and in containers. The vining or trailing varieties (the Mediterranean and Cora Cascade) are excellent for hanging baskets or hanging over the edge of a container; it is perfect for raised planters to display their colourful beauty on decks. Patios can be grown as houseplants, garden porches, window sills and balconies. Certain varieties can be grown as houseplants in brightly lit locations. Cut branches can be used in vase floral arrangements in the home. It is great as ground cover, planted en masse with different colours in mixed plantings. The flowers are attractive to pollinators and are adapted to pollination by long tongue insects, such as butterflies or moths. This species is also able to self-pollinate and will re-seed itself if the soil is loose. Self-compatibility and relatively high tolerance to disturbance have enabled the plant to spread from cultivation and become naturalised in many parts of the world. It is grown commercially for the floral and pharmaceutical industries.

Rose periwinkle thrives in full sun or partial shade. They tolerate dry soil but do poorly on wet sites. The evenly moist soil of a typical annual garden suits them best. Their tropical ancestry dictates a need for warmth. The secret for success with this plant is that it likes its feet warm; so don’t plant in cold soils. This sun-loving, heat-loving plant can’t tolerate cold soil and usually ends up with rotted roots. Essentially free from insects and diseases, Madagascar periwinkles thrive in full sun. A Madagascar periwinkle plant welcomes partial shade in hot climates.

Medicinal uses
In the field of medicine, many life-saving drugs have been developed from plants. In this category, few as successfully employed has the rose periwinkle, Catharanthus roseus.

The Madagascar periwinkle’s value is not limited to being ornamental. Its more important but often overlooked role is in medicine with an interesting history. There is much more to the Catharanthus roseus than meets the eye. Deep within the beautiful plant are chemical compounds that can heal people. The rose or Madagascar periwinkle plant contains so many powerful healing elements and is so effective at fighting diseases like cancer and diabetes, that some people consider it a miracle plant. Scientists who were intrigued by the fact that traditional Madagascar healers used it to help treat diabetes decided to research other potential medicinal uses for the plant in the 1950s. They discovered hidden treasures within Rose Periwinkle, in the form of chemicals they could use to create medicines for cancer patients.

Pink plant

Their discovery led to one of the most important medical breakthroughs of the twentieth century. The plant contains as many as 70 known alkaloids, many of which demonstrate medicinal value. These include the anti-cancer compounds vinblastine, and vincristine; and the blood pressure lowering compounds in rose periwinkle show benefits in regulating blood sugar and others are known to help reduce pressure. In its native Madagascar, traditional healers always use rose periwinkle as a remedy for a number of diseases such as high blood pressure, diabetes, asthma and menstrual problems. The plant has long been cultivated for herbal medicine and as an ornamental.

In Ayurveda (Indian traditional medicine), the extract of its roots and shoots, though poisonous, is used against several diseases. In traditional Chinese medicine, extracts from it have been used against numerous diseases including diabetes, malaria and Hodgkin’s lymphoma. In Jamaica, the plants use known as periwinkle tea is for diabetes. As it travelled farther and farther around the world, it became the miracle drug of folk medicine prescribed by herbalists in southern Africa, Australia and Philippines, for constipation, toothaches, malaria, and diabetes. Other folk uses of the plant include those for memory loss and circulatory disorders.

As modern chemotherapeutic medicines, both vincristine and vinblastine have been subsequently developed into portents to save lives from leukaemia and Hodgkin’s disease. Prior to the discovery of these extracts, a patient’s chance of surviving Hodgkin’s disease and pediatric leukaemia was one in 10. Today, nine of 10 patients survive those diseases. Extracts of the plants are also an effective treatment for other cancers such as testicles, lungs and breasts. This pretty plant from Madagascar gives us two very important cancer-fighting medicines and more. Traditional Madagascar healers used the rose periwinkle for treating diabetes. This led to its study by western scientists who then discovered its anti-cancer properties. Many agencies in the field of international intellectual property rights consider the development of rose periwinkle as a classic case of “biopiracy”.

White plant

The traditional native use of these plants has led to drug discovery without benefit to the natives who first used the plant. These medicines have proved very profitable for global drug companies, but virtually none of this money finds it way back to Madagascar, one of the poorest countries in the world. There are recent international agreements, which have tried to ensure that profits from the commercial development of animal and plant species return to the countries of origin.

One of such agreement is the convention on Biological Diversity, which seeks the “fair and equitable sharing of the benefits from the use of genetic resources,” together with the conservation of biological diversity and the sustainable use of its components. Tropical rainforests contain scores of other plants that may also provide miraculous medical treatments yet scientists have tested less than one per cent of rainforest plants. About 50 per cent of pharmaceutical drugs are derived from plants. Who knows if another ‘rose periwinkle’ is waiting to be discovered in the rainforest of Madagascar or in Nigeria?

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