Thursday 7 July 2022

Maidenhair Tree: An Ornamental, Sacred and Medicinal Living Fossil

Female tree with seeds enclosed by fleshy coat

Maidenhair Tree, scientifically known as Ginkgo biloba (etymology GING-ko bi-LOW-buh), is a medium-sized deciduous tree in the family Ginkgoaceae of Gymnosperms (groups of plants with naked seeds as they do not produce fruits). The botanical name is derived from the Chinese word ‘Ginkgo’ meaning silver apricot and ‘biloba’ meaning two lobes in the context of leaves. It is the lone surviving member of its family as all others have become extinct during the Pleiocene (5 to 2.58 million years ago) epoch in the geologic time scale due to climatic upheavals. The maidenhair trees are also witness to the existence of dinosaurs in the Jurassic Period (199 million to 145 million years ago).
Approximately 150-200 years old tree growing in Shimla

The maidenhair tree, considered a relic species, is known by many other common names such as Bal Kumari (in Hindi), Sacred Tree of the East, Tree Hair of Venus, Bearer of Hope, The Living Fossil, Yin Xing, etc. The name ‘Living Fossil’ comes from the fact that this tree has not changed much since its origin and evolution in the Permian period nearly 270 million years ago as is evident from the fossil records. The common name ‘Bearer of Hope’ was given to the plants of this species as they were the only survivors of the nuclear attacks in Japan in 1945. It is a sacred plant to the Buddhists and is cultivated extensively near monasteries in Japan, Korea, and China.
       Approximately 150-200 years old tree growing in Shimla

Morphological Characteristics
Maidenhair tree is a medium-sized tree growing up to 40 m tall and having a trunk diameter up to 4 m. The bark of this tree is light gray or grayish brown and longitudinally fissured in old plants. The crown is conical when young and becomes broadly ovoid in old mature trees. Two types of branches, long branches, and short branchlets are visible. Leaves have prominent petioles and pale green leaf blades, turning bright yellow in autumn to give a magnificent look to the trees. The leaf blades on the long branchlets are divided by a deep, apical sinus into 2 lobes (specific name is derived from this characteristic) and each lobe is further dissected. The leaves on short branchlets have undulate margin.
Fan-shaped leaves
Dried leaves of maidenhair tree

The maidenhair trees are dioecious (individual plants are either male or female) and produce either catkin-like male cones or single-seeded female cones enclosed by fleshy integument known as sarcotesta. The female plants are wind-pollinated in March-April and are self-fertile. Seeds are elliptic, ovoid, or subglobose, measuring up to 3.5 cm, and are enclosed by a fleshy yellow, or orange-yellow sarcotesta (modified fleshy integument). The fleshy sarcotesta emits a rancid odour when ripe in September or October.
Catkin-like male cones of maidenhair tree
(Photograph courtesy: Dr. Om Prakash Vidyarthi ji, Retd. IFS)


Mature seeds enclosed in orange-coloured fleshy sarcotesta
(Photograph courtesy: Sh. Om Prakash Vidyarthi ji, Retd. IFS)

USES

1. For Landscaping:
Maidenhair tree can tolerate a wide range of climatic and edaphic conditions, including pollution, and is cultivated as a landscape tree in many parts of the world. The bright yellow autumn colour of the leaves gives the trees a magnificent look.
Beautiful bright yellow autumn colour of Maidenhair tree growing in Cheshmashahi Botanical Garden in Srinagar (J&K)
(Photograph courtesy: Mr. Shayiq Rasool Kar, Deputy Director, Kashmir Department of Floriculture, Gardens & Parks, Srinagar)

2. As a Sacred Plant:
Maidenhair tree is sacred to Buddhists as is Peepal to the Hindus. It is frequently planted near Budhist monasteries in Japan, Korea, China, and other countries.

3. Medicinal Uses:
Ginkgo green tea

Maidenhair tree contains a diverse array of phytochemicals such as lactone derivatives (ginkgolides), ginkgo heterosides, bilobalides (terpene lactones) and flavonoids (flavonol and flavone glycosides). Other constituents are 6-hydroxykinuretic acid, catechin, isorhamnetin, kaempferol, protocatechuic acid, quercetin, shikimic acid, sterols and vanillic acid. These phytochemical constituents are responsible for the medicinal properties of the maidenhair tree. It has been suggested to use Ginkgo biloba in the form of tea, extract or other ready-made products. Some of the medicinal properties are listed below:

i. Memory Improvement: The leaves of maidenhair tree are considered a brain tonic. It is reported to improve age-related memory loss in old people. Ginkgo biloba is available as a single herbal formulation or in combination with other constituents. Mostly, mature leaves are used for medicinal purposes.

Ginkgo based herbal medicines
(Available on Tata 1mg)

ii. For Anxiety and Depression: Studies have reported that oral intake of extract of Ginkgo leaves gives beneficial results in elderly persons with anxiety related to cognitive decline. Its intake allays the symptoms of depression. 

iii. Regulation of Blood Circulation: It is reported to improve blood circulation in the brain due to the presence of high flavonoid content in the yellow autumn harvested leaves.

iv. Relief in Asthma: Intake of Ginkgo biloba leaves is beneficial in cough and asthma.  

v. Anti-microbial Properties: Plant extract has been reported to be anti-bacterial and anti-fungal. 

vi. Anti-Inflammatory Activity: The maidenhair tree is considered one of the best botanicals for reducing inflammation.

vii. For Cholesterol and Hypertension: 3-6 grams of leaves taken daily reduces the serum cholesterol and regulates the high blood pressure.

viii. Cure for Leucorrhoea: Roots of maidenhair tree are recommended as a cure for leucorrhoea.

4. As a Pesticide:
The leaves of the maidenhair tree are also used as a biopesticide.

5. As a Nut:
The seeds of the maidenhair tree are roasted to detoxify and eaten in China. Raw seeds contain toxic constituent ginkgotoxin, which has anti-vitamin B6 activity and inhibits gamma-aminobutyric acid (GABA) formation required for neurotransmission. The recommended dose per day is less than 15 grams of nuts.

A branch showing fissured bark

Cultivation
The maidenhair trees can be propagated through seeds or vegetatively through stem cuttings. Plants raised through seeds grow faster than the plants raised through rooting of stem cuttings.

Friday 1 July 2022

eFloraofIndia: One of the Largest Citizen Science Projects in the World

 


The twenty-first century is a century dominated by technology, which permeates every aspect of our lives. Information and Communication Technology (ICT) has been embraced by the plant sciences for data analysis, archiving, and retrieval. J.M. Garg Ji, an electrical engineer and alumnus of Panjab University, Chandigarh, founded a small Google group "Indiantreepix" on June 17, 2007, to discuss the identification and uses of trees that grow in different parts of India. Later, in order to make it more inclusive, the name was changed to "eFloraofIndia." Over time, more people like me joined, and as a result, its membership eventually grew to more than 3200 members from all around the world. eFloraofIndia celebrated the completion of its highly productive 15 years in June 2022.



Today, eFloraofIndia (eFI) is one of the largest and best resources available on India Flora on the web. It has a collection of more than 4,00,000 images of more than 14,000 species (out of the total of around 18,000 species found in India). eFI is a dynamic site where data is updated and improved continuously for about six hours virtually every day. The eFI website is regularly improved and updated by a group of pillars, moderators and experts. The precious resources of eFI are the images, which are shared by its members travelling to every nook and corner of India. The images are properly identified by a team of experts and given the final shape at the website. On the eFI website, all contributions are acknowledged. Botanists, taxonomic experts, bureaucrats, engineers, IT professionals, researchers, teachers, private professionals, doctors, students, and laymen are among the committed members of the group.


The best thing about the eFI database is that the taxa have been arranged in Family and genera pages on the website. The detailed discussions by experts can be seen on the species pages. Many photographs shared in the group for identification later became new species or additions to the Flora of India. Some species have been named after the names of eFI members as a due credit for bringing those species in the knowledge of taxonomic experts. A page on threated and endangered species of India is very informative and has links to the images of those plants contributed by its members.



Everyone will be amazed to learn that throughout the last 15 years, while constructing this largest citizen science initiative, not a single rupee has been collected from any source. The collective efforts of the group members are worth thousands of crores of rupees, if ever assessed in terms of money. But there is no way to quantify the devoted work that its members and specialists from around the world put in. It is a worthwhile lesson to be taught in colleges and universities as it provides an excellent example of one of the biggest citizen science initiatives in India.