Tuberose is a tropical perennial flowering plant that has found a special niche in the floriculture industry due to its sweet fragrance and elegant white flowers. The botanical name of tuberose is Polianthes tuberosa L. In India, it is also known as Rajanigandha or Nishigandha. The words Rajanigandha or Nishigandha refer to its nocturnal flowering habit, as the flowers emit a very strong and pleasing fragrance at night.
This plant belongs to the family Amaryllidaceae. Native to Mexico, it is grown extensively in tropical and subtropical regions. Its versatility in floral decorations, garland making, and the extraction of essential oils has led to its widespread commercial cultivation.
Tuberose flowers contain aromatic compounds that are highly sought after in the perfumery industry. Additionally, tuberose is used in traditional medicine, as its bulbs contain lycorine, which has therapeutic properties.
Origins of Tuberose
It is believed that tuberose originated in Mexico. It was grown by the Aztecs nearly 600 years ago. Spanish explorers brought this fragrant flower into Europe in the early 16th century. This became an ideal addition for moon gardens-orchards of white or pastel flowers that unfurl their strong fragrances at dusk. Victorian-era enthusiasts appreciated tuberose because of its beauty and scent.
Its popularity experienced a temporary fall due to its frequent use in funeral rituals. In the 16th century, it witnessed its introduction to India by European traders. It has been a dominant product since then in the floriculture industry here in India. India stands as one of the leading producers of tuberose at present, and flowers are highly valued for commercial use.
Varieties of Tuberose
Cultivars of Tuberose are also classified into several categories. They are primarily categorized into Single, Semi-Double, Double, and Variegated.
Pure white flowers are fragrant, with a single row of petals. These types of floriferous cultivars are grown widely for loose flowers, essential oil extraction, and garland making. Among these varieties are Single Mexican, Kalyani Single, Shringar, Prajwal, Arka Nirantara, and Hyderabad Single. Shringar is a hybrid out of these with slightly pinkish buds. It produces an immense quantity of flowers. These flowers are used by perfumery industries.
Semi-double types have two to three layers of petals. Both are commercially produced for steam distillation purposes and used as cut flowers. The Semi Double cultivar flowers at white with multiple corolla layers which also advances its aspect of ornamental.
Double-flowered types contain more than three layers of petals, and some have even tinge of pinkish red. These types are extensively used in cut flowers, bouquets, and in decoration purposes. Some of the popular varieties are Pearl Double, Kalyani Double, Swarna Rekha, Hyderabad Double, and Suvasini. Suvasini, developed by IIHR, Bangalore, produces more flowers per spike with uniform blooming, making it ideal for cut flowers. Vaibhav, also developed by IIHR, yields 50% more spikes than Suvasini and is preferred for commercial cultivation.
The variegated tuberose varieties provide ornamental appeal due to streaked leaves. Two major variegated varieties are Rajat Rekha and Swarna Rekha. They were developed through gamma irradiation at the National Botanical Research Institute (NBRI), Lucknow. Rajat Rekha is a single-flowered variety with silvery white streaks on the leaves and Swarna Rekha is a double-flowered variety with golden-yellow streaks along the leaf margins.
Comparison Among Cultivars
Among the single-flowered types, Shringar and Prajwal can be highlighted since they have very high yields with fragrance. The number of flowers that Shringar produces is 40% more than Single Mexican, hence making it more commercially viable. Prajwal is a cross between Shringar and Mexican Single. It produces 20% more yield than Shringar, and this is suitable for loose flower markets as well as for cut flowers.
Double-flowered varieties, Suvasini and Vaibhav, are widely preferred for their spike yield and floral appeal. Suvasini has uniform blooming patterns and is thus a good bet for cut flower arrangements. Vaibhav yields 50% more spikes than Suvasini, which makes it the better option for commercial growers.
In terms of concrete percentage, single-flowered varieties contain a higher percentage, ranging from 0.08% to 0.14%. The double-flowered varieties, such as Pearl Double, have lower concrete content. This makes Single Mexican, Shringar, and Prajwal the preferred choices for the perfume and essential oil industries.
Variegated varieties are mainly for ornamental purposes. They also contribute to the diversification of cultivating tuberose. Rajat Rekha and Swarna Rekha are also fit for cut flower utilization. The concrete content in Rajat Rekha is 0.089% more than that in Swarna Rekha, which is only 0.062%.
Tuberose, with its captivating fragrance and versatile uses, is highly valued in ornamental and commercial markets. Its demand for perfumery, floral design, and medicine continues to grow. Ongoing hybridization and research promise improved yields and fragrance quality, ensuring its enduring significance in horticulture.
