Turmeric: Curcuma longa
C. longa (Popularly known as Longa types)
- Nearly 40 species of Curcuma are known to exist in India, while only one species C. longa contributes to commercial production of turmeric of commerce (96%). It is an herbaceous perennial with under ground rhizomes. It is a sterile triploid (3n = 63) and do not normally set viable seeds.
- The other species are C. aromatica (Kasthuri manjal), C. caesia (Black turmeric), C. amada (mango ginger), C. zedoaria, C. purpurescens, C.mangga, C.heyneana, C. xanthorrhiza, C. aeruginosa, C. phaeocaulis and C. petiolata are also cultivated in different parts of India. C. aromatica is cultivated to a lesser extent for Kasturi turmeric used in cosmetics.
- Turmeric types can be grouped into three based on maturity period as short, medium and long duration types. Short duration types are known as Kasturi.
- They mature in seven months, rhizomes possess pleasant aroma, good yielders of dried turmeric and rich in volatile oil content but low in curcumin and used in culinary preparation.
- Flowering is common in these types and seeds produce gametic seedlings. Medium duration Kesari types which mature in eight months are referred as intermediary types and are high yielders of fresh rhizomes than Kasturi types and rich in curcumin and volatile oil.
- Long duration types mature in nine months and are moderately good both for rhizome yield and other quality constituents. Flowering and seed set are rare in medium and long duration types.
- The important characteristics of C. longa, C.aromatica, C. amada, C. angustifolia and C. zedoaria.
C.aromatica (Popularly known as Kasthuri types)
- Pseudostem is tall, robust with oblong elliptic leaves narrowed at the base. Plant reach a height up to 1m with 8 to 10 leaves. Spike is apical, length ranges between 10-18 cm. with pale yellow flowers.
- Starchy root tubers are not produced at the end of fibrous roots. Rhizomes are bigger in size with more curcumin content but moderate in volatile oil.
C. amada (Mango ginger)
- In this group, cultivars mature early, within 6-7 months. Pseudostem is short with elliptic/oblong leaves. Flowering is lateral, and being a tetraploid, fertile and viable seeds are produced.
- Plants produce peculiar root tubers at the end of the fibrous roots. Rhizomes possess pleasant unique aroma due to volatile oil but low in curcumin content.
- Rhizome production is less as compared to C. longa types. It is used in the preparation of dyes, cosmetics and drugs but not used as a spice or condiment.
- Popularly known as mango ginger cultivated in India for its rhizomes, which have the odour of raw mangoes and it is used for the preparation of pickles , chutneys etc.
- It is considered to be native of north- eastern India and to have spread in cultivation throughout the Indian subcontinent and Malaysia.
- The interior of the rhizome is yellow and when dried has an agreeable musky odour with a slight smell of camphor and a pungent bitter taste.Zedoary rhizomes are used in indigenous medicines in Asia and in perfumery in India.
- Among the characters, plant height, rhizome yield, curing percentage , curcumin content, oleoresin content and resistance to leaf blotch and leaf spot diseases recorded higher percentage of genetic advance indicating scope for selection.
- Estimation of oil and curcumin contents in different cultivars of C. longa and C. aromatica indicated that variability for oil and curcumin content was high in C. longa compared to C. aromatica and for identifying cultivars with high curcumin and oil content, it may be worth while to carry out selection in C. longa alone.
- Hybridization work is limited in turmeric as commercial cultivars are sterile triploids of C. longa.