Southeast Asia is a centre of diversity for the genus; several species have been found in northeast India

Scientists from the Botanical Survey of India (BSI) have discovered two new species of Zingiber, commonly referred to as ginger, from Nagaland. While Zingiber perenense has been discovered from the Peren district of Nagaland, Zingiber dimapurense was found in the Dimapur district of the State.

Details of both discoveries were published in two peer-reviewed journals earlier this year. Of the two species, Zingiber dimapurense is taller in size, with leafy shoots measuring 90-120 cm high, whereas the leafy shoots of Zingiber perenense reach up to 70 cm in height.

For Zingiber dimapurense, the lip of the flower (modified corolla) is white in colour, with dense dark- purplish red blotches. Its pollen is a creamy-white and ovato-ellipsoidal, whereas the fruit is an oblong 4.5 cm-5.5 cm long capsule. In the case of Zingiber perenense, which was discovered about 50 km from where the other species was found, the lip of the flower is white with purplish-red streaks throughout, and the pollen is ellipsoidal.

Specimens collected

The type specimens of Zingiber perenense were collected in September 2017, when botanists were working on the ‘State flora of Nagaland’ in the Peren district. “The plant was found growing in moist shady places on the bank of a small steam in the hilly terrain forest of the Tesen village under the Peren subdivision,” the publication authored by four botanists said.

The specimen of Zingiber dimapurense was collected in October 2016 from the Hekese village forest under the Medziphema subdivision. Some rhizomes of this plant collected along with field data were planted in the Botanical Survey of India’s Eastern Regional Centre garden in Shillong, where itself they began flowering in June 2018.

Centre of diversity

According to Dilip Kumar Roy, who has contributed to both the publications, the genus Zingiber has 141 species distributed throughout Asia, Australia and the South Pacific, with its centre of diversity in Southeast Asia. “More than 20 species have been found in northeastern India. Over the past few years, more than half a dozen species have been discovered from different States of northeast India only,” Dr. Roy said.

Previous discoveries of Zingiber include Hedychium chingmeianum from the Tuensang district of Nagaland, Caulokaempferia dinabandhuensis from the Ukhrul district in Manipur in 2017, and Zingiber bipinianum from Meghalaya in 2015.

Nripemo Odyou, another scientist with the BSI, who also contributed to both the new discoveries in 2019, said that the high diversity of ginger species in northeast India reveals that the climate is conducive for the growth and diversity of the genus.

More studies required

“Most species of ginger have medicinal values. More studies are required to ascertain the medicinal properties of the newly discovered species,” Dr. Odoyu said.

The rhizome of Zingiber officinale (common ginger) is used as a spice in kitchens across Asia, and also for its medicinal value. Botanists said that other wild species of Zingiber may have immense horticultural importance.