There are about fifteen species under the genus Polianthes, of which twelve species have been reported from Mexico and Central America. Of these, nine species have white flowers; one is white tinged with red and two are red. Except for Polianthes tuberosa L., all the others are found growing wild.
Varieties
There are four types of tuberoses named by the number of rows of petals they bear. They are,
• Single
• Semi-double
• Double and
• Variegated
A. Single: They bear pure white flowers with one row/ whorl of Corolla segment. Flowers are highly scented and are extensively used for loose flower purpose, essential oil and concrete extraction. Single types are more fragrant than double. Concrete content has been observed to be 0.08 to 0.11 per cent. Loose flowers are used for making floral ornaments. It’s floral buds are greenish white. Also, the per cent seed setting is high in a single. Single Mexican, Kalyani Single, Shringar, Prajwal, Arka Nirantara, Rajat Rekha, Hyderabad Single, Calcutta Single, Phule Rajani, Kahikuchi Single, Pune Single are main varieties.
Description of some important single varieties
1.Arka Nirantara
Arka Nirantara is released by Indian Institute of Horticultural Research (IIHR), Bangalore. It has white, single flowers with prolonged blooming.
2.Shringar
This tuberose hybrid has been developed from a cross between ‘Single x Double’ and was released by Indian Institute of Horticultural Research (IIHR), Bangalore. It bears single type fragrant flowers on strong and sturdy, medium spikes. The flower buds are attractive with slightly pinkish tinge. The spikes have some flowers, and the individual florets are larger and appealing compared to the local ‘single’ cultivar. Loose flowers of this hybrid can be used for garlands and extraction of tuberose concrete.
The spikes can also be used as cut flower. The loose flower yield of this hybrid is about 36 percent higher than the existing local single variety. The yield of loose flowers is about 15,000 kg/ha per year, which is 40% higher than ‘Calcutta or Mexican Single’, and the concrete content of the hybrid is at par with Mexican Single. Shringar is preferred by farmers and perfumery industries. This hybrid is tolerant to root knot nematodes (Meloidogyne incognita).
3.Prajwal
This hybrid which bears single type flowers on tall stiff spikes is a cross between ‘Shringar’ x ‘Mexican Single’. The hybrid was released by Indian Institute of Horticultural Research (IIHR), Bangalore. The flower buds are slightly pinkish, while the flowers are white. The individual florets are large, compared to ‘Local Single’. It yields twenty per cent more loose flowers than ‘Shringar’. It is recommended both for loose flower and cut flower purpose tuberose flowers yield.
4.Single Mexican
It is a single flowered variety. This variety produces maximum flowers during October-December, which is considered as lean months for tuberose flowers yield.
Semi-double
They consist of flowers bearing 2-3 rows of corolla segments on straight spikes. They are used for concrete extraction as well as for cut flowers. E.g. Cv. Semi Double bears white flowers with two to three rows of Corolla.
Double
They bear flowers having more than three rows of corolla segments on straight spikes. Flower colour is white and also tinged with pinkish red. The main varieties are Pearl Double, Kalyani Double, Swarna Rekha, Hyderabad Double, Culcutta Double, Vaibhav and Suvasini.
Description of some important double varieties
1.Suvasini
It is a double flowered multi whorled variety released by Indian Institute of Horticultural Research (IIHR), Bangalore. It is a cross between ‘Single’ and ‘Double’. This variety produces some flowers per spike. The spikes are best suited for cut flowers. This tuberose hybrid is multi-whorled with bold, large, pure white fragrant flowers borne on long spikes in contrast to off-white flowers of local cv. ‘Double’. The number of flowers per spike is more, and flower opening is uniform in this hybrid as compared to the local ‘Double’ cultivar. Spike yield is 26 percent more compared to the local ‘Double’ cultivar. Spikes are best suited for cut flower purpose.
2.Vaibhav
This hybrid which bears double flowers on medium spikes is from the cross ‘Mexican Single’ x IIHR – 2’ and was released by Indian Institute of Horticultural Research (IIHR), Bangalore. The flower buds are greenish in contrast to pinkish buds in ‘Suvasini’ and ‘Local Double’. Flowers are white. Spike yield is 50 per cent higher compared to ‘Suvasini’. Hence, recommended for cut flower purpose.
3.Pearl Double
The flowers tinged with red in the ‘Double’ type are known as ‘Pearl’. Pearl Double is high flower yielder with quality flowers. They are mainly used for cut flower and bouquet purpose as well as loose
flower and extraction of essential oil. Concrete recovery has been found to be 0.06%. It does not open well and is not commercially viable as the single cultivar.
Variegated
These are some streaked leaf forms, known as ‘variegated’. In these varieties, silvery white or golden yellow streaks are visible on leaves. National Botanical Research Institute, Lucknow has developed two
variegated varieties Rajat Rekha and Swarna Rekha by gamma irradiation.
1.Rajat Rekha
Rajat Rekha is a gamma ray induced mutant evolved by irradiating bulbs of the single flowered cultivar. It is a single flowered variety released by National Botanical Research Institute (NBRI), Lucknow. Flowers have silvery white streaks along the middle of the leaf blade. Concrete content has been found to be 0.089 per cent.
2.Swarna Rekha
It is a double flowered variety released by National Botanical Research Institute (NBRI), Lucknow. The flowers are double with golden yellow streaks along the margins of the leaf. It is a gamma ray induced mutant, in which mutation occurred in chlorophyll synthesis resulting in a change in leaf colour. Concrete content has been found to be 0.062 per cent.
Source-
MLA
“Tuberose — Vikaspedia.” Vikaspedia. N.p., n.d. Web. 08 Sep. 2017 <http://vikaspedia.in/agriculture/crop-production/package-of-practices/flowers/tuberose>.
APA
Tuberose — Vikaspedia. (n.d.). Retrieved from http://vikaspedia.in/agriculture/crop-production/package-of-practices/flowers/tuberose
- Central Coastal Agricultural Research Institute, Ela, Old Goa, Goa