Quorum Sensing in Bacteria

Quorum sensing is a sophisticated signaling mechanism employed by bacteria to regulate gene expression in response to population density. It enables bacteria to coordinate group behaviors, such as biofilm formation, virulence factor expression, and symbiotic relationships.

Key Components:

1. Autoinducers:
• Bacteria release small signaling molecules called autoinducers into their environment.
• Autoinducers accumulate as the bacterial population grows.
2. Receptor Proteins:
• Bacteria possess receptors that can detect the concentration of autoinducers.
• When the autoinducer concentration reaches a threshold (quorum), it binds to the receptors.

Function:

1. Gene Expression Regulation:
• Binding of autoinducers to receptors activates signal transduction pathways.
• This leads to changes in gene expression, influencing various cellular processes.
2. Coordination of Behaviors:
• Quorum sensing regulates behaviors that are more effective when executed by a population rather than by individual bacteria.
• Examples include the formation of biofilms, expression of virulence factors, and the establishment of symbiotic relationships.
3. Adaptation to Environment:
• Quorum sensing allows bacteria to adapt to changing environmental conditions collectively.
• It enhances survival and competitiveness in diverse ecological niches.

Examples:

• Vibrio fischeri: Bioluminescence in V. fischeri is controlled by quorum sensing, allowing the bacteria to emit light only when present in sufficient numbers.
• Pseudomonas aeruginosa: Quorum sensing regulates the production of virulence factors, contributing to the pathogenicity of this bacterium.

Applications:

• Understanding quorum sensing provides insights for controlling bacterial behaviours, offering potential strategies for disease control and biofilm management.

In conclusion, quorum sensing is a vital mechanism that allows bacteria to sense and respond to their population density, facilitating coordinated group behaviours essential for their survival and adaptation in diverse environments.

 

Gram Staining

 

Gram staining

Principle

When the bacteria is stained with primary stain Crystal Violet and fixed by the mordant, some of the bacteria are able to retain the primary stain and some are decolorized by alcohol. The cell walls of gram positive bacteria have a thick layer of protein-sugar complexes called peptidoglycan and lipid content is low. Decolorizing the cell causes this thick cell wall to dehydrate and shrink, which closes the pores in the cell wall and prevents the stain from exiting the cell. So the ethanol cannot remove the Crystal Violet-Iodine complex that is bound to the thick layer of peptidoglycan of gram positive bacteria and appears blue or purple in colour.

In case of gram negative bacteria, cell wall also takes up the CV-Iodine complex but due to the thin layer of peptidoglycan and thick outer layer which is formed of lipids, CV-Iodine complex gets washed off. When they are exposed to alcohol, decolourizer dissolves the lipids in the cell walls, which allows the crystal violet-iodine complex to leach out of the cells. Then when again stained with safranin, they take the stain and appear red in colour.

Procedure

1. Take a clean, grease free slide.
2. Prepare the smear of buttermilk or curd suspension on the clean slide with a loopful of sample.
3. Air dry and heat fix.
4. Crystal Violet was poured and kept for about 30 seconds to 1 minutes and rinse with water.
5. Flood the gram’s iodine for 1 minute and wash with water.
6. Then ,wash with 95% alcohol or acetone for about 10-20 seconds and rinse with water.
7. Add safranin  for about 1 minute and wash with water.
8. Air dry, Blot dry and Observe under Microscope.

Result

Violet coloured rod shaped gram positive  bacteria observed.

 

LAND DEGRADATION

The change in the characteristic and quality of soil which adversely affect its fertility is called as Degradation.

Land degradation means:

1. Loss of natural fertility of soil because of loss of nutrients.

2. Less vegetation cover

3. Changes in the characteristic of soil.

4. Pollution of water resources from the contamination of soil through which water sweeps into ground or runoff to the water bodies.

5. Changes in climatic conditions because of unbalanced created in the environment.

Causes of Land Degradation:

(a) Deforestation:Deforestation is taking place at a faster rate due to increasing demands of timber, fuel and forest products which results into degradation of land resources.

(b) Overgrazing:

Overgrazing refers to excessive eating of grasses and other green plants by cattle. It results into reduced growth of vegetation, reduced diversity of plant species, excessive growth of unwanted plant species, soil erosion, and degradation of land due to cattle movement.

(c) Agricultural practises:The modern agricultural practises, excessive use of fertilizers and pesticides has adversely degraded the natural quality and fertility of the cultivation land.

(d) Industrialization:

Development of industries for the economic growth of the country leads to excessive deforestation and utilization of land in such as way that it has lost its natural up gradation quality.

(e) Urbanization:Increasing growth of population and demand for more residential areas and commercial sectors is also one of the reasons for land degradation.

Prevention and Control Measures for Land Degradation:

Following are some practises for controlling land degradation:

1. Strip farming:

It is & practice in which cultivated crops are sown in alternative strips to prevent water movement.2. Crop Rotation:

It is one of the agricultural practice in which different crops are grown in same area following a rotation system which helps in replenishment of the soil.

3. Ridge and Furrow Formation:

Soil erosion is one of the factors responsible for lad degradation. It can be prevented by formation of ridge and furrow during irrigation which lessens run off.4. Construction of Dams:

This usually checks or reduces the velocity of run off so that soil support vegetation.

5. Contour Farming:

This type of farming is usually practiced across the hill side and is useful in collecting and diverting the run off to avoid erosion.

Land degradation is one of the world’s most pressing environmental problems and it will worsen without rapid remedial action. Globally, about 25 percent of the total land area has been degraded. When land is degraded, soil carbon and nitrous oxide is released into the atmosphere, making land degradation one of the most important contributors to climate change. Scientists recently warned that 24 billion tons of fertile soil was being lost per year, largely due to unsustainable agriculture practices. If this trend continues, 95 percent of the Earth’s land areas could become degraded by 2050.

 

LAND RESOURCES, LAND USAGE CHANGE

 LAND RESOURCES AND LAND USE CHANGE

The term “land resources” encompasses the physical, biotic, environmental, infrastructural and socio-economic components of a natural land unit, including surface and near-surface freshwater resources. Land resources include hills, valleys, plains, wetlands, river basins, etc. Throughout history humans have derived all the resources for human development and survival from land, such as food, water, fuel, agriculture, grazing, fishing , mining, etc. Industrial revultion is based on resources we get from land resources- Gold, iron, coal, diamond and oil.

LAND USE CATEGORIES

Major land-use categories are:

1. Forests: It is important to note that area under actual forest cover is different from area classified as forest. The latter is the area which the Government has identified and demarcated for forest growth. The land revenue records are consistent with the latter definition. Thus, there may be an increase in this category without any increase in the actual forest cover.
2. Land put to Non-agricultural Uses: Land under settlements (rural and urban), infrastructure (roads, canals, etc.), industries, shops, etc. are included in this category. An expansion in the secondary and tertiary activities would lead to an increase in this category of land-use.
3. Barren and Wastelands: The land which may be classified as a wasteland such as barren hilly terrains, desert lands, ravines, etc. normally cannot be brought under cultivation with the available technology.
4. Area under Permanent Pastures and Grazing Lands: Most of this type land is owned by the village ‘Panchayat’ or the Government. Only a small proportion of this land is privately owned. The land owned by the village panchayat comes under ‘Common Property Resources
5. Area under Miscellaneous Tree Crops and Groves (Not included in Net sown Area) : The land under orchards and fruit trees are included in this category. Much of this land is privately owned.
6. Culturable Waste-Land: Any land which is left fallow (uncultivated) for more than five years is included in this category. It can be brought under cultivation after improving it through reclamation practices.
7. Current Fallow: This is the land that is left without cultivation for one or less than one agricultural year. Following is a cultural practice adopted for giving the land rest. The land recoups the lost fertility through natural processes.
8. Fallow other than Current Fallow: This is also a cultivable land which is left uncultivated for more than a year but less than five years. If the land is left uncultivated for more than five years, it would be categorized as culturable wasteland.
9. Net Area Sown: The physical extent of land on which crops are sown and harvested is known as net sown area.

LAND USE CHANGES

Land use pattern changes mainly due to the following reasons:

1. Building homes

2. Developing industries

3. For making towns & cities

4. Making roads, railways, airports etc.

5. Building dams

IN-SITU & EX-SITU CONSERVATION

 CONSERVATION OF PLANT GENETIC RESOURCES

Plant genetic diversity is vulnerable to "genetic erosion", the loss of genes and alleles from populations, especially in locally adapted landraces. The replacement of local varieties with modern hybrid varieties and cultivars causes genetic erosion. This is intensified by the emergence of new pests, weeds, diseases, urbanization, and land clearing. 

There are two important methods of conservation.

1) In situ conservation

2) Ex situ conservation.

In situ conservation is the conservation of genetic resources at its original habitat as a natural population. An organism is conserved in the same area where it is naturally found. Examples are

Biosphere reserves, National parks, Wildlife Sanctuaries, and Biodiversity hotspots.

Biosphere reserves cover very large areas, more than 5000 sq. km. Currently, India has 18 BRs. Eg: Sundarbans (WB).

National Parks are regions that cover 100 to 500 sq. km. There are 103 NPs in India. Eg. Kaziranga- Assam- One Horned Rhino.

Wild Life Sanctuary- Aimed to conserve animal diversity, usually in small areas. There are 551 WLS in India. Eg- Aralam WLS - Malabar Civet.

Biodiversity hotspots - These are regions with at least 1500 vascular plants as endemics and 70% of the original habitat is lost. There are currently 36 hotspots all over the world, out of which 4 are in India. Eg: Eastern Himalayas, and Western Ghats.

Ex situ conservation

It is an 'off-site' conservation, in which an endangered species is protected outside its natural habitat, by removing or transferring the species from a threatened habitat. Botanical gardens, Zoos etc are examples. Lalbagh Bangalore, Royal Botanical Garden, Kew, etc.

Cryopreservation is another method of ex-situ conservation, in which seeds, pollen, tissues, and embryos are conserved in liquid nitrogen. 

Seed banks are also considered  as ex-situ conservation, in which dried seeds are stored in glass vessels or paper covers in a systematic manner.

ETHNOBOTANY AS A TOOL TO PROTECT INTERESTS OF ETHNIC GROUPS

Ethnobotany is the documentation of traditional knowledge of ethnic groups so that the valuable knowledge is not lost from the community as all the communities undergo changes in the due course of time. An ethnobotanist mainly documents the different tribes, ethnic groups, their life styles, plants used for various purposes, their traditions, beliefs etc. 

An ethnobotanist identifies the plants used by the tribes as medicine, food, fodder, and other miscellaneous uses. Indigenous knowledge is usually hidden among the ethnic groups, as they don't usually mingle with the external world. However, a few intelligent men intrude into these societies, steal their intellectual property, and take patents, in some distant place for the commercial use of the knowledge. In such cases, the original creator of the knowledge is the community and it is not properly benefitted. Such incidents have been reported from various parts of the world.

The popular cases of biopiracy of Azadirchta indica, Basmati rice, etc. are some classical examples. 

Azadirachta indica or Neem was used by the Indians from time immemorial but was not properly documented under the IPR. Some foreign company had taken a patent on the use of Neem which prevented all others from using the knowledge. In such cases, proper documentation of the indigenous knowledge is important. 

The Indian government has started a web initiative called TKDL - Traditional Knowledge Digital Library to document all such indigenous knowledge so that any patenting authority can inspect false claims made by frauds. Therefore, ethnobotanical documentation is very important for the interests of ethnic groups.

In addition there are Patenting Laws, IPR rules , etc to protect the interests of the ethnic groups. 

INTELLECTUAL PROPERTY RIGHTS (IPR)

The constitutional right granted by the government of a country to the creator or owner of any intellectual property to exclude others from using the same commercially for a given period of time is called Intellectual Property Right. It is framed for the benefit of all inventors, creators, writers, etc. to get a fare share of it's commercial use in the name of copy rights. 

The creator gets exclusive rights for his / her intellectual property, that is a creation of the mind or brain, such as a poem, a story, a logo, a painting, a scientific discovery or a cooking recipe. No one can use the same concept without legal consent of the original creator as per the Intellectual Property Rights (IPR). 

Traditional knowledge also come under IPR system. It is usually the biopirates, who steal traditional knowledge such as the uses of some plants for specific diseases and market it commercially by making modern medical combinations. 

The following categories are generally included in the IPR system.

1. Industrial designs.

2. Literary and artistic works.

3. Scientific discoveries.

4. Performances of performing artists. 

5. trade marks, logos, commercial names, designations etc.

6. traditional knowledge.

IP is divided into two categories for ease of understanding: 

1. Industrial Property 2. Copyright

Industrial property, which includes inventions (patents), trademarks, industrial designs, and geographic indications of source; and Copyright, which includes literary and artistic works such as novels, poems and plays, films, musical works, artistic works such as drawings, paintings, photographs and sculptures, and architectural designs. 

Properties are of two types - tangible property and intangible property i.e. one that is physically present and the other which is not in any physical form. Building, land, house, cash, jewelry are few examples of tangible properties which can be seen and felt physically. IP is intangible property.

The different types of Intellectual Property Rights are: 

i. Patents - Mainly given for discoveries eg: Electric Bulb, Car Engine, etc.

ii. Copyrights - Given for Stories, poems, etc.

iii. Trademarks- Given for trade names, product names etc. represented by TM

 iv. Industrial designs 

v. Protection of Integrated Circuits layout design 

vi. Geographical indications of goods - Ususally given to products from a specific geographical place. eg: Marayur Sharkara, Kasaragod Saree, Arnmula Kannadi, Darjeeling tea, Kanjipuram silk, Nagpur orange. 

vii. Biological diversity 

viii. Plant varieties and farmers rights 

IPR acts in India:

1. Indian Patents Acts, 1970

2. Indina Patents (Amendment) Act, 1999.

PARTICIPATORY FOREST MANAGEMENT

 Participatory forest management is a strategy to protect the forest and its resources with the help of local people residing nearby the forest. It has been considered the most effective strategy for forest management and conservation. Participatory forestry enables the involvement of people who have a direct stake in the forest and its resources in taking decisions regarding the forest, managing the forest and its resources, and formulating institutional frameworks for various forest-related programs. 

The inclusion of local communities in the conservation and management of the forest has been common for the last 25 years. Almost all countries in Africa and many in Asia are promoting Participatory Forest Management (PFM). Many countries are developing their national policies to include PFM as their plan of action.

The shift to PFM by the government is mainly due to the following aspects:

1. It is a more effective way of forest management as local people know the pulse of the forest, than any unknown newly recruited official.

2. It reduces the role and cost of the state in forest management.

3. It ensures livelihood for local people, as they get rewards from the government as honorarium. 

4. It is an effective method of decentralization of power.

5. The local people are more skilled 

6. it ensures a philosophical and psychological commitment of people in conserving the forest.

Roles of the people in PFM

1. Some local people, such as elders, teachers and local leaders can serve as a source of information regarding the forest. They have knowledge about the forest and they understand the needs of the local people. These people are a valuable source of information, hence called Key Informants.

2. People who share similar interests in the locality is treated as Interest Groups. An interest group can be formed based on age, gender, ethnic group etc. For example, a group of women who collect wood and honey from the forest or poor farmers in the locality.

The local people can be assigned the following duties:

1. Assessors of forest resources.

2. Decision makers of forest rules.

3. Implementers of forest action plans.

4.  Protectors of forest resources.

5. Silviculture breeders, experimenters etc.

6. Marketers of timber from forest.

History of PFM:

The local tribes of India had been suppressed intensely by various types of rules such as the Mughals, the British and even during early days of Independence. The Mughal rulers were unable to rule the tribes due to inaccessibility of the area. The tribals used 'warfare and withdraw' strategy to protect the forest resources from the Mughals. It was more aggressive with the entry of the British rulers. They tried to impose colonial rule on the tribals and extract revenue through 'Zamindars'. The tribals reacted violently and caused the Chur Rebellion which lasted from 1767 to 1980. It was the first ever rebellion against the British rule in India. But the British overpowered the tribes. 

The forest communities were further affected when Sal trees (Shorea robusta) were cut for making railway sleepers to expand the railway network. 

Post-Independence, India drafted the first Forest Policy in 1952, which proposed a functional classification of forests Protected forests, National forests, Village forests and tree-land. 

People's protests for forest conservation:

During 1970- 80, logging of trees for industrial purposes increased drastically and the people of Uttaranchal protested which was called Chipko Andolan. The villagers hugged the trees so as to prevent their cutting. As a result, the government of Uttar Pradesh imposed a 15 -year ban on tree felling.

The Arabari Experiment:

Forest officers of the Arabari region, of Midnapur district in West Bengal, recognized the role people can play in restoring degraded forests. They issued the first government order to include local people in protecting the forest. In return, 25% of the revenue obtained from the sale of timber resources was given to the locals.  This successful experiment led to the evolution of PFM concept.

The present state of PFM:

Today in India, we have 63618 forest protection committees spread over 27 states protecting 14 million hectares of forest.  

BIOPIRACY

When indigenous knowledge or a biological resource is used without the consent of the local people or the original inventor, it is considered Biopiracy. Many such cases have occurred in the case of patents; where private companies take the patent of indigenous knowledge such as to make medicines and commercialize it without the consent of the ethnic groups. It is an intellectual-level fraud for making a profit from bio-resources and indigenous knowledge.  

Biopiracy is a situation in which indigenous knowledge of nature, originating from indigenous people, is used by others for profit without their permission or without providing compensation to them.

A few cases of biopiracy are mentioned below;

1. Patenting of Azadirachta indica

The people of India have been using neem for time immemorial for various purposes. Indians shared the knowledge to all the world, however pirating this knowledge, the USDA and an American Multi National Company W. R. Grace got a Patent (No.0426257B) from the European patent Officer on the "method of controlling the plants by the aid of hydrophobic extracted from neem oil. 

2. Patenting of Basmati Rice:

Basmati is a long grained aromatic rice traditionally cultivated in North India. In 1997 the US patenting and trademark office granted a patent of Basmati to an American company named Rise Tec Inc. The company claimed that they invented the rice variety! 

3. Rice Biopiracy:

A biotech company Syngenta had signed an MOU with Indira Gandhi Agricultural University to access Dr. Richcharia's (former director of Central Rice Research Institute and known as the Rice sage of India) priceless collection of 22,972 varieties of rice. 

ROLE OF ETHNIC GROUPS IN CONSERVATION OF PLANT GENETIC RESOURCES

The ethnic groups living in different parts of the world play a crucial role in the conservation of plant genetic resources. Many tribal societies have practices of worshipping nature. They believe that the earth does not belong to any single individual, but the generations to come also have rights in it. The famous quote by a Red Indian Tribal Chief is relevant in this scenario: "Only when the last tree has been cut down, the last fish has been caught and the last stream poisoned, Will we realize that we can not eat money."

About 300 million indigenous people are living in the world, of which 150 million live in Asia and 68 million live in India. There are 227 ethnic groups and 573 tribal communities in India belonging to Negroid, Proto- Australoid, Mongoloid, Mediterranean, West Breachy and Nordic racial stocks. They treat the forest as a shelter and eat forest resources. They protect plants based on their beliefs and uses.

List of plants conserved by ethnic groups:

Plants conserved based on a belief

1. Mangifera indica- (Anacardiaceae)- to worship Lord Vidhyadhara

2. Terminalia arjuna- (Combretaceae)- Lord Brahma.

3. Citrus medica- (Rutaceae)- Lord Brihaspati

4. Aegle marmelos- (Rutaceae)- Lord Shiva

5. Azadiracta indica- (Meliaceae)- Serpent King Nagaraja

6. Ocimum sanctum- (Lamiaceae)- Goddess Lakshmi

7. Nerium indicum- (Apocynaceae)- Lord Ganesh

8. Calotropis gigantea- (Asclepiadaceae)- Lord Shiva

Crop plants conserved by tribals

1. Amorphophallus paenonflodium- Araceae- Petiole /bulb as vegetable

2. Achyranthes aspera- Amaranthaceae- Vegetable

3. Bauhinia purpurea- Fabaceae- Leaf as vegetable.

4. Dioscorea alata- Dioscoriaceae- Tuber is edible.

5. Curculigo orchioides- Amaryllidaceae- Tuber is edible & medicine.

Plants protected in sacred groves

1. Alstonia scholaris- Apocynaceae

2. Helicteres isora.

3. Rauvolfia serpentina

4. Vateria indica

Plants used for snake bite as antidote

Acorus calamus, Bauhina purpurea, 

PLANTS USED BY TRIBALS

 1. FOOD PLANTS

The tribal people mainly depend on forest plants for their food requirements. In India about 800 edible plants are used by various tribal populations. Tribals collect various parts of the plants growing in forests such as fruits, flowers, seeds, young shoots, leaves, etc for eating. The following are examples

LEAF

Achyranthes aspera- Amaranthaceae- Young leaves.

Basella rubra- Basellaceae- Leaves

Bauhinia purpurea- Fabaceae- Leaves

Pouzolzia zeylanica- Urticaceae- Leaves.

Cannabis sativa- Bhang- Leaves and tender shoot- Rajasthan.

FRUIT

Aegle marmelos- Rutaceae.

Diospyros melanoxylon- Ebenaceae- 

INTOXICANTS & BEVERAGES

    Intoxicants or the beverages consumed by tribals for intoxication are of various types depending upon the plant from which they are obtained and the process of preparation. Women and children also consume these beverages during religious ceremonies or festivals. Moreover, these drinks also play a supplementary role for tribal people and are also used in small quantities as medicine for various ailments by different tribes. For example, rice beer is used as an intoxicant by most tribals in India and it is also used for medicinal purposes as a light tranquilizer, for treatment of fever, dysentery, diarrhea, and gynecological disorders.

1. Borassus flabellifer 

Family: Arecaceae 

This plant is commonly known as the ‘Asian Palmyra Palm’ or ‘Toddy Palm’ or ‘Wine palm .The sap of this plant is used by the tribals for making an alcoholic drink called ‘tadi.’ The sap is obtained by tapping the shoot top and collecting it in earthen pots. It is fermented before consumption.

2. Cannabis sativa 

 Family: Cannabaceae 

 A beverage called bhang lassi is prepared from the female flowers, especially during festivals. The buds along with leaves are crushed in a pestle and mortar, the paste is added to milk or curd and filtered, finally it is flavored with sugar, fruit and spices. Consumption of this beverage is part of ancient Hindu culture.

3. Eleusine coracana 

 Family: Poaceae

 An alcoholic drink called ‘paise’ is prepared from the grains of this plant. A fermented paste prepared from the grains of wheat or maize is used to make this liquor. This beverage is prepared fresh or a day earlier and tribal men, as well as women, consume at least, as well as women, one litre per head in the morning before going to fields for work. 

4. Ficus hispida 

Family: Moraceae

 Country liquor is prepared from this plant by tribals of Orissa. Tribals of Meghalaya use unripe fruit as vegetable. The fruit juice is used for various medicinal purposes also.

5. Madhuca longifolia

 Family: Sapotaceae

Dried corollas or flower buds of this plant are  fermented to obtain an alcoholic drink called ‘mahua’ which is very popular among the tribals of India. Gond and Kol tribes also use it for treating dysentery.

RESINS

Resins can be defined as oxidation products of various essential oils.

1. Gardenia resinifera 

Family: Rubiaceae 

Uses: Members of Gond tribe use resin obtained from the stem and buds of this plant as insecticide and repellant for flies. 

2. Butea monosperma 

Family: Fabaceae 

The gum resin is of ethno-medicinal importance and is used as tonic. It has diuretic and astringent properties.

3. Shorea robusta 

Family: Dipterocarpaceae. 

Sal resin is applied for relief from chest pain and cramps.

4. Pinus roxburghii 

Family: Pinaceae 

Besides being commercially important, pine resin has local medicinal uses also.It is used for treatment of boils, bone fractures, swellings, ulcers, urinary complaints and sprains.

OILS

1. Allium sativum 

Family: Liliaceae 

Oil obtained from garlic bulb is rich in sulphur and has strong antimicrobial activity .It is used by Indian tribals for head massage to treat headache. Gond tribes use it.

2. Azadirachta indica 

Family: Meliaceae 

Oil obtained from the seeds is called neem oil which is very aromatic.It is used for treatment of skin problems such as itching, healing of cuts and wounds.

3. Madhuca indica 

Family: Sapotaceae 

Oil is edible, commonly known as ‘garang’,’ idum’ or ‘mahua tel’. It is used as hair oil & lamp oil.

4. Ricinus communis 

Family: Euphorbiaceae 

Castor oil obtained from the seed of this plant is used by tribals for treating disorders like rheumatism, constipation and worm infestation.

MISCELLANEOUS- Religious and Cultural

Ficus religiosa- Peepal or Bodhi tree- 

Ficus benghalensis- Banyan tree

Aegle marmelos- Found in Shiva temples

Saraca indica- In Hinduism, this tree is associated to the God of Love, also known as the Kama Deva.

Azadirachta indica- associated with goddess Durga and many people believe that neem trees help in keeping evil spirits away.

Ocimum sanctum- Tulsi- used in temples.

Phyllanthus emblica- Chyavanprash

Cocos nucifera- in temple rituals.

INDIA AS A MEGA DIVERSITY NATION

The term megadiverse country refers to any nation that harbours the majority of Earth's species and high numbers of endemic species.The UNEP (United Nations Environment Programme) has recognised 17 Megadiversity Nations across the world. India is one among them due to its commendable diversity of organisms. 

India has 4 out of 34 globally identified  Biodiversity Hotspots (Himalaya, Western Ghats, Indo-Burma, and Srinlanka- Sundaland). India has wide range of habitats- The varied edaphic, climatic and topographic conditions and years of geological stability have resulted in a wide range of ecosystems and habitats such as forests, grasslands, wetlands, deserts, and coastal and marine ecosystems. Arid, semi- arid and desert regions occupy 38.8% of India's land mass with 682 species of which 6% is endemic. This area is also rich with cat type predators- Lion, Leopard and Tiger. The Great Indian Bustard is a threatened bird living in this habitat. 

The cold Himalayan region covers 5.8% of the geographical area. The cold desert also harbors endangered species such as snow leopard, yak and Asiatic ibex.  

India has a good collection of wetland habitats as well with about 4500 square kilometers of Mangrove ecosystem. The fish and bird diversity is high in such regions.  We have 783 fresh water fishes, of which 223 are endemic. India has good fish diversity and the country is one of the largest fish producers of the world. 

India has a lengthy coastal habitat of 7500 kilometers, with diverse habitats like estuaries, lagoons, backwaters, salt marshes and coral reefs. These habitats are also rich in species diversity.

India has diverse forest habitats, consisting of 23.5% of total land mass of which 75% are located in North East states India. India has 16 major forest types. The mountain ecosystem of India consists of forest ecosystems. Western Ghats and Eastern Himalayas are rich in diversity of species with 40% of endemism. 

Considering the major categories of life forms, India has the following diversity:

Animals

1. Protists- 2577 (out of 31,200 in the world)
2. Mollusca- 5070 (out of 81,000)
3. Arthropoda - 68300 ( out of 9,90,000)
4. Fishes- 2546 (out of 30,000)
5. Amphibia- 209 (out of 6200)
6. Reptiles- 456 (out of 8200)
7. Birds- 1232 (out of 9900)
8. Mammals- 390 (out of 5490)

Plants (As per 2007 data)

1. Algae- 6500 (out of 40,000)
2. Bryophytes - 2825 (out of 17000)
3. Pteridophytes- 1200 (out of 13000)
4. Gymnosperms- 48 (out of 980)
5. Angiosperms- 18000 (out of 2,50,000)

Microbes

1. Bacteria- 850 (out of 8500)
2. Fungi- 14500 (out of 72000)
3. Virus- 1200 (out of ????? not estimated) as per 2019 data
4. Lichens - 2000 (out of 35000)

 

GRASSLAND ECOSYSTEM

Grassland is an area where the vegetation is dominated by grasses, that is members of  families Poaceae and Cyperaceae etc. The vegetation is characterized by a continuous cover of grasses. Grasslands receive up to 150 cm rainfall per year. The temperature in this region varies from 15 to 35 degree Celsius. The dry season lasts for nearly 8 months,  making it the longest phase of a grass land. The grasses dominate in this region because rain fall is not sufficient to support the growth of trees and  other larger species. 

Grasslands are mainly categorized in to two:

1) Tropical grasslands

2) Temperate grasslands

Tropical grassland

Tropical grasslands are those distributed in the tropical countries of the earth. They are popularly known as Savannah. Fire is a frequent character of this grassland. The major species of the vegetation include grasses, Acacia and palms. These grasslands are well known through various television channels such as Discovery, National Geographic and Animal Planet. This habitat provides a lot of stories of predation and survival. 

The largest of savannah is located in Africa, especially central part of the continent such as Kenya, Tanzania etc. They are also found in Brazil. In India, the Banni Grassland Reserve is located in Gujarat. The soil in savannah is porous, which promotes rapid drainage of water, therefore only a thin layer of humus is present. 

Animals occurring in the tropical grasslands include, lion, cheetah, leopard, hyena., elephant, giraffe, rhinoceros, ant eaters and African mole rats.

Temperate grassland

Temperate grasslands are those distributed in the temperate zone of the earth. The temperature in the winter falls below minus 10 degrees, while summer is very hot reaching 35 degrees. Rainfall ranges between 25 to 100 cm in a year. Fire is very frequent, often initiated by lightening and therefore tall trees are unable to sustain.

Temperate grasslands are called in different names in different countries. For example, Prairies in North America, Steppes in Russia, Pampas in Argentina and Veldt in South Africa. Prairies are grasslands with tall grasses while steppes are grasslands with short grasses. The soil is deep, dark, and nutrient rich. The rotting roots of the grasses hold the soil and prevent erosion. 

The vegetation include tall grasses such as Andropogon gerardii, Panicum, Switch grass etc. The animals include Kangaroo in Australia, Pronghorn antelope in North America, Horses in Europe, gazelles, buffaloes, saiga antelope and many smaller animals.

Importance

1. Good centers of carbon sequestration. 

2. Grasslands begin the food chain in the ecosystem.

3. Helps for domestication of many helpful animals such as buffaloes, horses, ass and cow.

4. Prevents soil erosion.

DESERT ECOSYSTEM

Desert is a terrestrial ecosystem which receives very little, lesser than 25cm per year, rainfall or precipitation. Deserts cover as much as one fifth of the earth's land surface and forms one of the major ecosystems on earth. 

Examples : Namib desert, South Africa. 

                    Atacama desert, South America

                    Sahara desert, Africa

                    Thar desert, India - Pakistan

The word comes from a Latin word desertum which means 'to abandon'.

Desertification is an ongoing process, though we don't realize it on a real time basis. We can sense the rise in atmospheric temperature, lack of rain etc., which will gradually lead to the formation of new deserts. Ancient civilizations of Greece, Mesopotamian and Mayan were demolished by the process of desertification.

Life is difficult in desert habitats, challenged with dehydration, lack of drinking water, extreme heat and sweat, lack of biodiversity which leads to lack of food material etc. Many of the organisms which survive on the deserts have specific adaptations for its survival. The camel has a bump on its back for storage of fat (NOT WATER) and they can live many days without eating anything. Their nose is adapted to prevent sand entering while sand storms. webbed feet to prevent sinking in to the sand and long eye lashes for preventing sand entering eyes.

Deserts can be classified in to two types;

1) Hot Deserts

2) Cold Deserts

Hot Deserts

Hot deserts are places with very high temperature as high as 50 degree Celsius in the day and freezing cool in the night. The soils are nutrient poor. They are found around latitude 20-30 degrees north and south of the equator. They occupy nearly 20% of the earth's surface. 

Exaples include Sahara, Atacama of Chile, Kalahari of Africa and Simpson of Australia.

The plants of the hot desert include succulents such as cactus, annuals, desert shrubs such as Fonquieria splendens. The cactus can store water. Many plants have volatile chemicals to prevent herbivores.

Animals include ants, birds, rodents, lizards, snakes, small mammals etc. Examples - Horned viper, Addax antelope, Ostrich, Camel, Golden Jackal etc.

Cold Deserts

The day time temperature in cold deserts can be around 2-4 degree Celsius, though it can raise upto 26 degrees in summer. In winter, the temperature is as low as minus 26 degrees. Precipitation is less than 25 cm per year. They show the formation of ice coated regions during winter. 

Examples-  Gobi desert, Mongolia; Great basin desert, North America; Patagonian desert, Argentina.

Succulents are absent in cold deserts, as they are susceptible to freezing. Many species have spines and shed leaves. Examples- Artemesia, Sagebrush etc

Animals live in burrows to escape the cold weather. Examples- Jack rabbit, Pocket mice, Kit fox and Coyote.

Importance

1. Deserts account for one sixth of world's population.

2. They cover one fifth of land mass.

3. Formation of minerals via dehydration- example Gypsum, borates, nitrates.

4. Carbon sequestration- The cyanobacteria in deserts store CO2 from air.

ETHNOBOTANICAL ASPECTS OF PLANTS- RAUVOLFIA SERPENTINA

Rauvolfia serpentina, known in multiple common names- Sarpagandhi, Sarpagandha, Indian Snakeroot, Devil Pepper etc- is one of the ancient plant widely used by humans since ages. 

Scientific Name: Rauvolfia serpentina (L.) Benth. ex Kurz.

Family: Apocynaceae

Habitat: Moist shady places near forests of India, Srilanka and Indonesia. 

There are nearly 100 species of  the genus Rauvolfia, a member of the milkweed family Apocynaceae. These plants are characterised by the presence of milky latex in stem and leaves. 

Morphology: The plants are sub-shrubs, with watery latex. Simple leaves with whorled (3-4 leaves) phyllotaxy. Cymose inflorescence. Petals white and fruits are crimson red.

Uses: 

The plant is widely used in modern medicine, ayurvedic, unani  and folk medicine as well. 

1. It is used in treating hypertension, eg. BP Care & Cure made by German's company.

2. It is used for insomnia, i.e., is lack of sleep. 

3. Used for central nervous system diseases.

4. Used as a tranquilizer, in case of anxiety related issues, for example Alprazolam tablets and Zolfresh tablets.

5. Root extract is used for intestinal disorders, such as dysentery and diarrhea. 

6. Used in treating hysteria and schizophrenia. 

Constituents:

The constituent is Reserpine. In addition, a lot of other secondary metabolites are present in Rauvolfia- Ajmalicine, Ajamaline, Chandrine, Renoxidine, Serpentine and tetraphyllicine. 

ETHNOMEDICINAL PLANTS- INDIGOFERA TICTORIA നീലയമരി

Indigofera , belonging to family Fabaceae, is a popular plant used by humans since ages for extraction of the blue dye Indigo. The plant is believed to be used in Egyptian mummies before 4000 years.   The dye is obtained from its leaves. 

Morphology: Indigo is an erect, profusely branched herb which grows up to 2 meters. Leaves are pinnately compound, 9-13 leaflets opposite, elliptic, base and apex rounded. Inflorescence is raceme, flowers reddish, standard, wing and keel petals present, fruit is a pod, maximum 12 seeds are found in a pod.

Habitat: Widely cultivated.

Uses:

1. Main source of Indigo dye, which is called 'King of dyes'

2. It is used aa green manure in coffee plantations.

3. It is used as tooth brush.

4. Leaf extract is used to cure burns and wounds of horses, cattle and sheep.

5. Root is used for tooth ache.

6. Antidote for snake bite, scorpion bite etc.

7. Tanzanians use it for syphilis and gonorrhoea. 

ETHNOBOTANICAL ASPECTS OF PLANTS- PONGAMIA PINNATA

Pongamia pinnata, also known as Indian beech tree or Pongam oil tree, is commonly seen in mangrove forests and deciduous forests of the Indo-Malayan region. It is a fast growing medium sized tree which is evergreen by nature. In Malayalam, it is called 'Ungu'. 

Morphology: Evergreen trees reaching up to 20 meter height. Leaves are imparipinnate, alternate arrangement, 5-7 leaflets are present, pubescent, ovate, acuminate apex, leaf margin entire, calyx 5, petals 5, stamens 10, monadelphous, ovary inferior with single chamber, fruit is a pod, reniform seeds.

Habitat: Deciduous and mangrove forests.

Uses:

1. Potential source of biodiesel.

2. Traditional medicine for bronchitis, whooping cough and rheumatism.

3. Used in itches and skin diseases.

4. Bark used for piles when bleeding.

5. Used as remedy for diabetes.

6. Roots used for cleaning gum and ulcer.

ETHNOBOTANICAL ASPECTS OF PLANTS- TRIBULUS TERRESTRIS

Tribulus terrestris, commonly known as Devil's Thorn is a plant belonging to family Zygophyllaceae.  It is distributed in temperate and tropical regions such as Europe, Africa, Asia, New Zealand and Australia. It grows abundantly in  dry deciduous forests, wastelands and road sides. 

Morphology: They are prostrate herbs with opposite leaves. Leaflets are in 4-5 pairs, each leaflet has a length of 1.5 cm. Flowers are golden yellow, with 5 petals, 10 stamens, 5 stigmas and 5 lobed ovary. Fruit has spines. 

Constituents: Spirostanol, furostanol and saponins.

Uses: 

1. Tribulus is used to increase athletic performance, body building etc.

2. They are used to puncture the tyres of bicycles, hence called 'puncture wines'.

3. It is used for kidney problems such as kidney stones.

4. Used as 'diuretic pill' to increase urine production.

5. Used for skin disorders such as eczema, psoriasis and scabies.

6. For heart and circulatory issues such as  high cholesterol.

7. It is used for digestive issues such as flatulence, constipation and intestinal worms.

8. Used for nose tumor and stomatitis (inflammation of mouth).

9. A powerful male sexual stimulant acting as 'herbal Viagra" and improving sperm quality.

10. Female sexual health, to reduce issues with menopause such as hot flushes, depression, negative thinking and emotional stress.

 

ETHNOBOTANICAL ASPECTS OF PLANTS- GLORIOSA SUPERBA

Gloriosa superba is a well known ornamental plant widely cultivated in Indian houses. The plant belongs to family Liliaceae and commonly called as Glory Lily. It is a native to tropical Africa and  tropical Asia. It is a tuberous climbing plant with attractive red flowers with striking wavy yellow margins. It flowers from November to March every year. The plant is toxic in nature and can harm animal life if used in very large quantity, all parts of the plant being poisonous. 

Habitat: A native of tropical Asia and Africa, it is found through out India (from the Himalayas to the Deccan ) . It is found throughout  Western Ghats, Madagascar Islands and Srilanka. 

Morphology: The wines of the plant are tall, though weak stemmed, with tuberous roots. The tips of the leaves are spirally twisted and forms the tendril to climb other plants and elevated objects. Leaves are lanceolate and acuminate. Flowers are large and solitary. Six refxed petals are seen in each flower. The petals hang down during initial stages and become erect when mature. The ovary is exposed and the flower produces five long stamens. 

Components: Colchicines and gloriosines.

Uses: 

1. The poisonous nature of the plant has given a notorious reputation for the plant as it is widely used for suicid purpose. It causes vomiting and stomach ache. 

2. It is used as ornamental plants.

3. Every part of Gloriosa is used  for medicinal purposes.

4. It is used in Ayurveda for ulcers, laxative, abortifacient and leprosy infection.

5. It is also used in piles.

6. Tubers have anti-fertility effect.

ETHNOBOTANICAL ASPECTS OF PLANTS- VITEX NEGUNDO

Vitex negundo, (Chinese chastetree) a member of family Verbenaceae, known commonly as Nirgundi or Kari Nochi, is distributed all over India. 

Habitat: It is common in the riverbanks, road sides etc. It is native of Africa and Asia. Found mostly in India, Burma, Afgan, China, Srilanka, and Malaysia.

Morphology: Vitex is a shrub having a purplish pubescent shade all over. It has aromatic and pale bark. Leaves are 3-5 foliate. Length of leaflet varies from 5-14. Elliptic or lanceolate leaves are seen. Inflorescence is a panicle having length up to 20 cm. Calyx has 5 sepals, corolla is purple in color, upper lip 2-lobes and lower lip 3-lobes. Stamens-4, filaments purple. Style purple, stigma bi-fid and fruit is a purple or black  drupe.

Constituents: Casticin, chrysosplenol and vitexin. 

Uses: 

1. Chasteberry is known as a female remedy, used to reduce sexual desire. Roman wives kept the leaves of chasteberry  on their couches, when their husbands were abroad, that's the reason why the plant is known as chasteberry tree. 

2. The plant is also used in monastries, as it reduced sexual desire, and became a spice food where it was called "Monk's pepper".

3. It is used from ancient times to regularize monthly periods and treat dysmenorrhea. It also eases menopause symptoms. 

4. It reduces ear pain when mixed with mustard oil and used as an ear drop. 

5.   It is supposed to decrease obesity. A spoonful of juice from the leaves of Vitex taken orally for this purpose. 

6. It is used to treat diabetes, in combination with Catharanthus, and Azadirachta.

7. It is a household pesticide an also used in witchcraft. 

8. Herbal shoes are prepared from vitex to treat rheumatism in Chattisgarh, India. 

9. It was used for punishment in ancient China.

10. It is believed to repel 'evil eye' by the Oroan tribe.

11. It is used as a totem plant for defeat in war. The winning army used to wear Cardiospermum halicabacum, while those who lost the war were supposed to wearthe flowers of  Vitex. 

12. Vitex is considered as a biological indicator for the presence of water.

13. It is used as hedge plant, as no animal feeds on it.

14. Fresh leaves are used to mask the smell of rotting meat, when boiled with it.

15. Dry leaves are used for storing woolen garments as they repel insects.

16. Leaves are burnt to repel mosquitoes and other smokes.

17. The Lodha tribe uses dry leaf to repel bedbugs.

18. Green leaves are used as green manure. 

19. It is used as a medicine for several diseases of cattle. 

20. It enhances memory.

21. The leaf paste is applied on the navel and vagina for easy delivery.

22. In Ayurveda it is used to make Nirgundi taila, Nirgundi ghritha etc.

23. There is a local saying, "A man can not die of disease in a place where Vitex, Adathoda and Acorus are found".