Crotalaria retusa is a perennial herbaceous plant native to tropical Africa and Asia. It belongs to the family Fabaceae. It grows well in warm climates and requires little maintenance.
Common names include Devil's bean, Rattlepod, rattlebox, rattleweed, and wedge leaf rattlepod. Rattlepod is a plant that has small seeds inside a pod which rattles when shaken. The name comes from the sound they make when shaken.
It is used as a source of food and medicine in traditional African herbalism. Its leaves are rich in vitamins C and E, calcium, iron, magnesium, phosphorus, potassium, sodium, zinc, and copper. They also contain tannins, saponin, glycosides, flavonoids, alkaloids, anthraquinones, steroids, amino acids, and essential oils.
Crotalaria retusa grows well in warm climates and requires little water. It also tolerates drought conditions. As a result, it is widely cultivated throughout the tropics.
Crotalaria retusa contains alkaloids such as crotalineine, crotamine, and retusine. The main alkaloid is pyrrolizidine alkaloids. These compounds may be responsible for the toxic effects observed when consuming the plant. The main alkaloid found in C. retusa is retusine, which has been shown to cause convulsions, paralysis, and death in animals.
Crotalaria and butterflies
The yellow flowers of this plant contain alkaloids, flavonoids, saponins, tannins, and triterpenes. These compounds have anti-inflammatory properties and may be useful against cancer. Butterflies also use these compounds to protect themselves from predators.
The plant Crotalaria retusa attracts butterflies because they use the nectar from flowers to feed its larvae. This plant has been used for centuries to attract butterflies.
They are often used as food plants by the larvae of some Lepidoptera species.
Common tiger, Plain tiger, and Common Indian crow are some butterflies that are frequent visitors.
These butterflies visit the plants to sequester chemical substances which help in the biosynthesis of a pheromone component which is important for the courtship and mating process.
Medicinal properties of Crotalaria
1. Anti-inflammatory Properties
Studies suggest that C. retusa contains compounds that inhibit the production of pro-inflammatory cytokines. Researchers believe that these compounds may prevent the development of chronic inflammatory disorders.
2. Antibacterial Activity
The extracts of C. retusa have antibacterial activity. Researchers found that the extract inhibited the growth of Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Proteus vulgaris.
3. Diarrhea Treatment
A study conducted in Nigeria showed that the leaf extract of C. retusa was effective in reducing the severity of diarrhea. Another study indicated that the seed extract reduced the duration of diarrhea.
4. Skin Care
Scientists tested the anti-wrinkle effects of C. retusa on mice. Their results suggested that the plant extract improved skin elasticity and prevented damage to collagen fibers.
5. Asthma Relief
One study investigated the effect of C. retusa leaf extract on asthmatic rats. The researchers concluded that the extract had bronchodilating properties.
6. Cancer Prevention
The leaves of C. retusa contain flavonoids, which are antioxidants. Flavonoids help protect against cancer because they block the formation of free radicals. Free radicals are molecules with unpaired electrons that can damage DNA and other cellular components.
7. In addition, its roots are used as a remedy for coughs and colds, asthma, bronchitis, fever, malaria, stomach ulcers, diabetes, hypertension, heart disease, cancer, arthritis, rheumatism, gout, kidney stones, urinary tract infections, skin diseases, eczema, psoriasis, ringworm, fungal infections.
8. Other Uses
Other studies show that C. retusa has potential uses beyond its traditional medicinal applications. For example, it could be used as a source of fiber or feedstock for biofuels. Its leaves contain saponins, which make it useful in soap making. It is also used as a natural insecticide, fungicide, bactericide, nematocide, acaricide, larvacide, ovicidal, pheromone and repellent.
Side effects of C. retuda are unknown. However, some side effects associated with other Crotalaria species include Nausea, vomiting, abdominal pain, headache, dizziness, drowsiness, insomnia, blurred vision, dry mouth, constipation, increased appetite, decreased appetite, and weight loss.
How to Grow Crotalaria Retusa Plants
Crotalaria retusa grows best in full sun but will tolerate partial shade. It needs well-drained soil rich in organic matter. Water regularly during the growing season. When the weather turns hot, water more often. If you live in an area where temperatures drop below freezing at night, cover your plants with a blanket or plastic sheet until spring arrives.
You can propagate C. retusa by taking cuttings from new shoots in early spring. To take a cutting, first remove about 1/2 inch of bark from the stem. Then insert the tip of a sharp knife into the center of the wound. Cut down to just above a node. Remove any dirt around the base of the stem. Place the cut end of the stem in moist sand or perlite. Keep the cut end submerged in water. Cover the pot with clear plastic wrap. Change the water every day. After two weeks, transplant the cuttings into individual pots filled with fresh soil.
You don't need to fertilize Crotalaria retusa unless you notice yellowing foliage or poor growth.
Dr. Vandana K.