Strobilanthes kunthiana - The plant that blooms every 12 years.

Neelakurinji by Rakesh Dogra

INTRODUCTION

Strobilanthes kunthiana, commonly known as neelakurinji, is a shrub of the family Acanthaceae. The flowers bloom once every 12 years. It belongs to the genus Strobilanthes which has around 450 species and was first described by Christian Gottfried Daniel Nees von Esenbeck in the 19th century. Out of 450 species, 148 are found in India. The blooming cycle varies with species ranging from a year to 16 years.

DESCRIPTION

Neelakurinji usually grows 30-60 cm in length but can grow beyond 2 metres if the conditions are favourable for that. The stems are glabrous(free from hairs) to pubescent (covered with fine, short hairs). The shape of the leaves can be elliptic or obovate. For detailed morphological characteristics, click here or here. The flowers are light blue in the beginning but turn purple-bluish at maturity. It is found in the Shola forest of Western Ghats of India at an altitude of 1300-2400 metres.

(A. Blooming in habitat; B. Inflorescence; C. Onset of fruiting; D. Capsules; E. Seeds.)

Strobilanthes kunthiana by Rajeev Singh

MASS FLOWERING & MASTING

S. kunthiana is a plietesial plant(blooms at long intervals). It shows synchronous mass flowering, i.e., all the individuals of a group bloom nearly at the same time. As a result of synchronous mass flowering, it exhibits masting or mass seeding which is the production of seeds in huge numbers.

There are 2 main hypotheses that try to explain the importance of mass flowering and masting of this shrub. They are:

1. Outcrossing hypothesis: It explains that synchronised flowering allows cross-pollination in these plants. Cross-pollination leads to diversity in plants and in turn, high-quality seeds.

2. Predator satiation hypothesis: This hypothesis explains that synchronous reproduction in certain species produces more seeds than the seed predator can consume. This ensures the survival of the seeds.

MEDICINAL PROPERTIES

S. kunthiana is believed to have many medicinal properties such as antibacterial, antimicrobial, antiviral, antifungal, antiseptic and many more. Bees are the main pollinators of this plant which means they also make honey from the nectar collected from Neelakurinji's flowers. The honey produced from the Neelakurinji flower is known as "Kurinjithen honey" and is believed to be beneficial in treating heart blockages.

CONSERVATION STATUS S. kunthiana is an endangered shrub. Human activities, natural calamities, increased pollution, manmade summer fires and plantations of tea, eucalyptus, and black wattle in its habitat are the major threats to it. That's why, to ensure its long-term protection, Kurinjimala Sanctuary is set up in the Idukki district of Kerala.

References : •https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:55761-1 •https://bnrc.springeropen.com/articles/10.1186/s42269-020-00379-9 •https://en.m.wikipedia.org/wiki/Strobilanthes_kunthiana