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Names and Synonyms

Common Names

• Blackboard Tree
• Milkwood Pine
• White Cheesewood
• deviltree
• ditabark
• milkwood-pine
• milky-bean
• milky-pine
• pali-mari
• palmira alstonia
• white-pine
• Chatim
• Common Alstonia
• Pulai Tree
• Indian devil tree
• Milky Pine

Scientific Names

Accepted name

Synonyms

• Echites scholaris
• Pala scholaris
• Alstonia scholaris var. velutina
• Alstonia kurzii
• Echites pala
• Alstonia scholaris var. avae
• Alstonia scholaris var. blumei

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant belongs to the kingdom Plantae and is classified under the phylum Streptophyta and the class Equisetopsida. Within the subclass Magnoliidae, it is situated in the order Gentianales and the family Apocynaceae. Ultimately, its specific taxonomic designation falls under the genus Alstonia.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a diverse geographical range across several key regions in Asia. In China, its distribution extends through the South-Central, Southeast, and Hainan areas. Moving toward the Indian Subcontinent, the species can be found growing in the state of Assam. Additionally, it is also naturally occurring within the borders of Bangladesh. Collectively, these locations highlight the plant's presence across both East and South Asian landscapes.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Alstonia scholaris is characterized by its specific altitudinal distribution, which dictates its presence within various forest ecosystems. This species typically thrives within a defined elevational range, occupying habitats from a minimum altitude of 300 m AMSL to a maximum of 1000 m AMSL. Within this vertical gradient, the plant maintains a mean elevation of approximately 650 m AMSL, a zone that likely represents its optimal ecological niche for growth and survival. This distribution pattern suggests an adaptation to the specific climatic and soil conditions found in mid-elevation tropical or subtropical forest zones.

Elevational range max:

1000 m AMSL

Elevational range mean:

650 m AMSL

Elevational range min:

300 m AMSL

Life history

The life history of Alstonia scholaris is characterized by its status as a perennial species, ensuring its long-term presence within its ecosystem. As a phanerophyte, the plant maintains its buds well above the ground, typically developing into a large, robust tree structure. Its physiological nature is classified as evergreen, meaning it retains its foliage throughout the year rather than undergoing seasonal shedding. Additionally, within its structural growth patterns, it exhibits traits consistent with a nanophanerophyte, reflecting its ability to maintain significant woody biomass as it matures through its life cycle.

Deciduousness :

evergreen

Life form :

nanophanerophyte

Life form :

phanerophyte

Lifecycle :

perennial

Morphology

The morphology of Alstonia scholaris is characterized by its significant stature and robust structural development, typically growing as a large, woody tree. It is a self-supporting plant that reaches substantial heights, with an average height of approximately 30 m and a maximum potential height of up to 36 m. As a strictly terrestrial species, it does not exhibit aquatic or semiaquatic tendencies, nor does it function as an epiphyte or a climber; rather, it maintains an independent growth habit without being an obligatory or facultative parasite. The plant's architecture is defined by its woody nature, providing the necessary stability to support its massive vertical growth in its natural habitat.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

tree

Parasite :

independent

Plant height max:

36 m

Plant height mean:

30 m

Woodiness :

woody

Physiology

The physiology of Alstonia scholaris is characterized by a C3 photosynthetic pathway, reflecting its metabolic strategy for carbon fixation. Its foliage is composed of elliptic-shaped leaves with entire margins, notably lacking any thorns or spines. The leaf dimensions exhibit significant variability, with lengths ranging from a minimum of 7 cm to a mean of 17.5 cm, reaching a maximum of 28 cm, while leaf widths vary from 2 cm to a maximum of 11 cm. The plant's resource allocation and leaf efficiency are indicated by its Specific Leaf Area (SLA), which fluctuates between a minimum of 131.277027 cm²/g and a maximum of 184.75 cm²/g, with a mean value of 158.0135135 cm²/g. Furthermore, the structural integrity of the plant is supported by a stem specific density (SSD) of 468 mg/cm³. Notably, this species does not function as a nitrogen fixer, relying instead on external soil nitrogen availability for its nutritional requirements.

Leaf form :

elliptic

Leaf length max:

28 cm

Leaf length mean:

17.5 cm

Leaf length min:

7 cm

Leaf margin :

entire

Leaf spines :

no

Leaf thorns :

no

Leaf width max:

11 cm

Leaf width min:

2 cm

Nitrogen fixer :

no

Photosynthetic pathway :

C3

Specific Leaf Area (SLA) max:

184.75 cm²/g

Specific Leaf Area (SLA) mean:

158.0135135 cm²/g

Specific Leaf Area (SLA) min:

131.277027 cm²/g

Stem specific density (SSD) mean:

468 mg/cm³

Reproduction

Reproduction in Alstonia scholaris is characterized by a diverse range of dispersal strategies, exhibiting an unspecialized dispersal syndrome that incorporates anemochorous, zoochorous, autochorous, and hydrochorous mechanisms. The seeds produced by this species demonstrate significant variability in weight, with a recorded minimum seed mass of 0.002 g and a maximum seed mass of 0.0133 g. On average, the seed mass is approximately 0.00765 g, reflecting a reproductive strategy designed to utilize multiple environmental vectors for effective colonization and distribution.

Dispersal syndrome :

anemochorous

Seed mass max:

0.0133 g

Seed mass mean:

0.00765 g

Seed mass min:

0.002 g

Sources: Global Inventory of Floras and Traits (GIFT)

Plant Parts

Alstonia scholaris has 2 reported plant parts identified across 18 scientific publications and several other databases that are studied for medicinal purposes. The most consistently reported plant part include leaf, stem.

Leaf

1. Molecules (Basel, Switzerland)
2. Organic letters
3. Organic & biomolecular chemistry
4. Pharmaceutical biology
5. The Journal of organic chemistry

Stem

1. Turkish journal of pharmaceutical sciences
2. Natural product research
3. Biochemistry and biophysics reports

Chemicals

Alstonia scholaris has 38 reported phytochemicals identified across 18 scientific publications and several other databases. The most consistently reported chemicals include Betulin, Echitamine, Lupeol, Picrinine, Scholaricine.

Betulin

1. Dr. Duke
2. Molecules (Basel, Switzerland)
3. Journal of applied toxicology : JAT

Echitamine

1. Toxicology letters
2. Integrative cancer therapies

Lupeol

1. Molecules (Basel, Switzerland)
2. Integrative cancer therapies

Picrinine

1. Journal of separation science
2. Journal of ethnopharmacology

Scholaricine

1. Journal of separation science
2. Journal of ethnopharmacology

Ursolic acid

1. Molecules (Basel, Switzerland)
2. Journal of applied toxicology : JAT

betulinic acid

1. Dr. Duke
2. Molecules (Basel, Switzerland)

triterpenoids

1. Journal of applied toxicology : JAT
2. Organic letters

19-EPI-SCHOLARICINE

1. Journal of separation science

3-Hydroxy-11-ursen-28,13-olide

1. Molecules (Basel, Switzerland)

Activities

Alstonia scholaris has 33 reported activities identified across 18 scientific publications and several other databases. The most consistently reported activities include Anthelmintic, Antibacterial, Anticancer, Antimicrobial, AntiHIV.

Anthelmintic

1. Dr. Duke
2. Journal of parasitic diseases : official organ of the Indian Society for Parasitology
3. Journal of advanced veterinary and animal research

Antibacterial

1. Dr. Duke
2. Molecules (Basel, Switzerland)
3. Organic letters

Anticancer

1. Dr. Duke
2. Journal of ethnopharmacology

Antimicrobial

1. Organic letters
2. Journal of ethnopharmacology

AntiHIV

1. Dr. Duke

Anticarcinomic

1. Dr. Duke

Antiedemic

1. Dr. Duke

Antifeedant

1. Dr. Duke

Antiflu

1. Dr. Duke

Antifungal

1. Journal of advanced veterinary and animal research

Conditions

Alstonia scholaris has 43 reported investigations on conditions identified across 18 scientific publications and several other databases. The most consistently reported conditions include malaria, cancer, Candida albicans, Plasmodium falciparum, asthma.

Malaria

1. Journal of ethnopharmacology
2. BMC complementary and alternative medicine
3. Journal of Ayurveda and integrative medicine
4. Integrative cancer therapies

Cancer

1. Advanced biomedical research
2. Journal of ethnopharmacology
3. Integrative cancer therapies

Candida albicans

1. Fitoterapia
2. Journal of advanced veterinary and animal research

Plasmodium falciparum

1. Turkish journal of pharmaceutical sciences
2. Planta medica

Asthma

1. BMC complementary and alternative medicine
2. Journal of ethnopharmacology

Bronchitis

1. BMC complementary and alternative medicine
2. Journal of ethnopharmacology

Lung diseases

1. Natural products and bioprospecting
2. Journal of ethnopharmacology

Oxidative stress

1. Phytomedicine : international journal of phytotherapy and phytopharmacology
2. Phytochemistry

Respiratory diseases

1. Journal of ethnopharmacology
2. Natural products and bioprospecting

Covid-19

1. Infection and drug resistance

Preparations

Alstonia scholaris has 28 reported preparations identified across 18 scientific publications and several other databases. The most consistently reported preparations include As.Cr, Capsule of alkaloids from the leaf of Alstonia scholaris (L.) R.Br. (Apocynaceae) (CALAS), Chloroform:methanol fractions, Methanol extracts, alcoholic extract.

As.cr

1. Phytotherapy research : PTR

Capsule of alkaloids from the leaf of alstonia scholaris (l.) r.br. (apocynaceae) (calas)

1. Pharmaceutical biology

Chloroform:methanol fractions

1. Pharmaceuticals (Basel, Switzerland)

Methanol extracts

1. Planta medica

Alcoholic extract

1. Advanced biomedical research

Alkaloid fraction of alstonia scholaris (asers)

1. Cancer biotherapy & radiopharmaceuticals

Alkaloidal extract

1. Journal of chromatography. B, Analytical technologies in the biomedical and life sciences

Alkaloidal leaf extracts

1. Journal of chromatography. B, Analytical technologies in the biomedical and life sciences

Bark

1. Chemotherapy

Bark extract

1. Biochemistry and biophysics reports