Basic techniques of plant tissue culture

Basic techniques of plant tissue culture

Techniques of plant tissue culture

Techniques of plant tissue culture are listed below:-

1. Culture vessels

The culture vessels used for plant tissue studies includes Erylenmayer flask (conical flask), petri plates and culture tubes (25 x 150mm).

2. Culture medium

The important media used for all purpose experiment are Murashige and Skoog medium (MS medium), Gamborg medium (B5 medium), White medium (W medium) and Nitsch medium.

The culture medium is closed with cotton plug/ or aluminium foil sheet. The pH of the medium is adjusted to 5.8 (acidic range).

3. Sterilization

Sterilization is the technique employed to get rid of the microbes such as bacteria and fungi in the culture medium and plant tissues.

So, it is important to sterilize the culture medium and plant tissue.

The culture medium can be sterilised by keeping it in an autoclave and maintaining the temperature of 121’C for 15 minutes.

The plant tissue (inoculum) is to be surface sterilised.

Chemical sterilization

By treating the inoculum in any one of the chemical sterilizant such as Sodium hypochlorite, Calcium hypochlorite, Mercury chloride for 15 to 20 minutes followed by repeated washing in sterile water upto 3 to 5 times.

4. Inoculation

Transfer of explant (root, stem, leaf, etc.) on to a culture medium is called inoculation.

The inoculation is carried out under aseptic condition for which an apparatus called laminar air flow chamber is used.

Flamed and cooled forceps are used for transfer of plant materials to different culture media kept in glasswares.

5. Incubation

The culture medium with the inoculum is incubated at 26 + 20C with the light intensity at 2000 to 4000 lux (unit of intensity of light) and allowing photoperiod of 16 hour of light and 8 hours of darkness.

6. Induction of callus

Due to activity of auxins and cytokinins, the explant is induced to form callus.

The callus is an unorganized mass of undifferentiated tissue.

The mechanism of callus formation is that auxin induce cell elongation and cytokinin induces cell division as a result of which masses of cells are formed.

7. Morphogenesis

Formation of new organs from the callus under the influence of auxin and cytokinin is called morphogenesis.

Roots and shoots are differentiated from the callus.

Such embryos are called somatic embryos result in the formation of young plantlet.

There are two types of morphogenesis

a. Organogenesis

Formation of new organs such as shoot and root is known as organogenesis.

The development of shoot from the callus is called caulogenesis and formation of root is called rhizogenesis respectively.

b. Embryogenesis

Formation of embryos (ie. bipolar structure having shoot and root) from the callus is called embryogenesis.

These embryos arise from somatic callus tissue and are called somatic embryos or embryoids or somaclonal embryos.

8. Hardening

Exposing the plantlets to the natural environment in a stepwise manner is known as hardening.

Finally the plantlets are gradually transferred to the soil.

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Recombinant DNA technology

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Gene transfer in plants, Cutting of DNA, Advantages of recombinant DNA

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Transgenic plants – Herbicide resistance in transgenic plants

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Practical application of genetic transformation

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Plant tissue culture – origin and techniques

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Status of tissue culture technology in India And application

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Protoplast fusion and Practical applications

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Single cell protein and its uses

Structure of DNA

Structure of DNA

DNA and RNA are identified in the nucleus.

They are complex macro molecules and made up of millions of smaller units called nucleotides.

Hence, DNA is a macromolecular substance with double stranded polynucleotide.

Each nucleotide is made up of pentose sugar, a phosphate group and a nitrogenous base.

Ribose is the constituent sugar in RNA and Deoxyribose in DNA.

The nitrogenous bases are of two kinds – purines and pyrimidines.

Adenine and guanine are the purines and thymine and cytosine are pyrimidines.

The nitrogenous bases found in DNA are adenine, guanine, cytosine and thymine, whereas in RNA thymine is replaced by uracil.

The sub-unit containing only sugar and nitrogenous base is known as nucleoside.

A nucleoside combines with phosphate to form a nucleotide. Thus, four kinds of nucleotides are seen in DNA molecule.

They are adenine nucleotide, guanine nucleotide, thymine nucleotide and cytosine nucleotide.

Hence, nucleotides are building blocks of DNA.

DNA – Structure of DNA 

In 1953, James Watson and Francis Crick proposed double helix DNA model on the basis of x-ray diffraction studies with photographs of DNA taken by Wilkins and Franklin.

DNA is a double stranded structure in which the two strands are coiled around each other forming a double helix.

The DNA duplex is “coil of life”.

There are two grooves found in DNA molecule namely major and minor grooves.

The backbone of the helix is formed of sugar and phosphate molecule.

The nitrogenous bases are attached to sugar molecules.

The two nucleotide strands are held together by unstable hydrogen bonds.

Erwin Chargaff in 1949 showed that

(i) The bases pair in specific manner. Adenine always pairs with thymine and guanine pairs with cytosine.

(ii) Total amount of purine nucleotides is always equal to the total amount of pyrimidine nucleotides i.e.[A] + [G] = [T] + [C].

(iii) The proportion of adenine is equal to thymine and so also of guanine is equal to cytosine.

But the [A] + [T] need not necessarily be equal to [G] + [C].

These empirical rules regarding the composition of bases in DNA is collectively known as Chargaff’s law or Base pair rules.

There are two hydrogen bonds between adenine and thymine (A= T) and there are three hydrogen bonds between guanine and cytosine (G≡C) pairing.

The two strand run antiparallely in opposite directions ie. they run in opposite direction 5’ to 3’ end and 3’ to 5’ end.

The two strands are interwined in clockwise direction. The width of DNA molecule is 20 A.

The strand completes a turn every 34 A along its length. There are ten nucleotides per turn.

The internucleotide distance is 3.4 A. Watson and Crick model of DNA is called B-form DNA.

The chains in B-form DNA are in right handed orientation.

Functions of DNA

It controls all the biochemical activities of the cell.

They carries genetic information from one generation to other. It controls protein synthesis and synthesize RNAs.

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STRUCTURE OF CHROMOSOME – CELL BIOLOGY

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Types of chromosomes with special types

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Gene and genome

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Linkage and mechanism of linkage

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Crossing over, gene mapping and recombination of chromosome

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Mutation and classification of mutation

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Mutagenic agents and its significance

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Structural Chromosomal aberrations

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Numerical chromosomal aberrations

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Role of DNA 

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Replication of DNA

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Structure of RNA and Types of RNA

Botanical description of Hibiscus rosa sinensis

Hibiscus rosa sinensis

Botanical description of Hibiscus rosa sinensis

Hibiscus rosa sinensis General Characters

Habit

Perennial shrub.

Root

Tap root system.

Stem

Aerial, erect, cylindrical, woody and branched.

Leaf

Simple, Alternate, petiolate, stipulate, serrate, glabrous, apex acuminate with multicostate reticulate venation.

Inflorescence

Solitary cyme and axillary.

Flower

Pedicel jointed, bracteate, bracteolate, bisexual, large, showy, pentamerous, dichlamydeous, actinomorphic, complete and hypogynous and mucilage is present in floral parts.

Epicalyx

5 to 8 bracteoles outer to the calyx. They are green and free.

Calyx

Sepals 5, green, gamosepalous showing valvate aestivation and odd sepal is posterior in position.

Corolla

Petals 5, variously coloured, polypetalous but fused at the base and showing twisted aestivation.

Androecium

Numerous stamens, monadelphous, filaments are fused to form a staminal tube around the style.

Staminal tube is red. Anthers are monothecous, reniform, yellow, transversely attached to the filament, dehisce transversely and extrorse.

Floral diagram

Hibiscus rosa sinensis

Gynoecium

Ovary superior, pentacarpellary and syncarpous.

Ovary pentalocular with many ovules per locule on axile placentation.

Style simple, long, slender and passes through the staminal tube. Stigma 5, capitate and coloured.

Fruit
Mostly abortive.

ECONOMIC IMPORTANCE of Malvaceae

1. Fibre plants

Gossypium barbadense (Egyptian cotton), G. hirsutum (American cotton), G. herbaceum (Cotton) and several other species of Gossypium yield cotton fibres of commercial value.

The fibres are obtained from the surface of seeds. Hibiscus cannabinus (Deccan hemp) yields bast fibres which are used for making ropes.

2. Food plants

The tender fruit of Abelmoschus esculentus (lady’s finger) is used as vegetable.

The leaves and sepals of Hibiscus sabdariffa (A kind of ‘pulichai’) are used for making pickles, jam and jelly.

A delicious ‘chutney’ is prepared from the leaves and sepals of H. cannabinus (Pulichai keerai) and H. sabdariffa.

3. Timber Plants

Timber obtained from Thespesia populnea (portia tree) is useful for making boat, furniture and agricultural implements.

4. Medicinal plants

Root and leaves of Abutilon indicum (Thuthi) and Malva sylvestris are used against fever.

Roots of Malva sylvestris and Althaea rosea are used for treating whooping cough and dysentery respectively.

5. Ornamental plants

Althaea rosea (Hollyhock), Hibiscus rosa sinensis (Shoe flower) H schizopetalus (A kind of shoe flower with dissected petals) are grown in gardens.

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QUESTION:

1. Write a note on androecium of Hibiscus rosa sinensis.
2. Describe the gynoecium of Hibiscus rosa sinensis.
3. Mention the binomial of any three medicinal plants of
4. Draw the floral diagram and write the floral formula of Hibiscus rosa sinensis.
5. What is epicalyx? It is present in Abutilon indicum?
6. Give a detailed account on economic importance of Malvaceae.
7. Describe Hibiscus rosa-sinensis in botanical terms.

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TAXONOMY OF ANGIOSPERMS, TYPES OF CLASSIFICATION

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BIOSYSTEMATICS NOMENCLATURE

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BINOMIAL NOMENCLATURE, ICBN

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HERBARIA AND ITS USES IMPORTANCE OF HERBARIUM

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Bentham and Hooker’s classification of plants

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Dicot Families – MALVACEAE

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Solanaceae – Datura metal and Economic importance

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Euphorbiaceae and Ricinus communis and its Economic importance

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Musaceae – Musa paradisiaca and its Economic Importance

Timber yielding plant – Teak

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Its binomial is Tectona grandis. It belongs to Verbenaceae. It is large
deciduous tree and shows resistance to termites.

Sap wood is white and heart wood is green emitting fragrance. The timber retains its fragrance for a long time.

It is hard , durable and strong and also takes up good
polishing.

In India, it is used for making furnitures, buildings, cardboards,
railway sleepers, etc.

Ships and bridges are also made from this timber.

Economic importance

• Teak wood is durable and it is an important timber in the tropics. As
  the seasoned teak, timber does not shrink, crack or alter its shape, it is extensively used in making household furnitures.
• It is also used in ship building, boats, etc.
• It is used for interior decoration.
• It is used for the manufacture of boards.

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Plant physiology – photosynthesis and its significance

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BIOLOGY IN HUMAN WELFARE Introduction & Food production

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Aims of plant breeding

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Aspects of plant breeding and Types

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Hybridization in plant breeding

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Polyploid breeding, Mutation breeding, Breeding for disease resistance

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Genetic engineering, Improved varieties, Role of biofertilizers

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Green manuring, Mycorrhiza as biofertilizer

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Benefits from biofertilizers

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Crop diseases and their control, Rice – Oryza sativa

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Groundnut or peanut – Arachis hypogea

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Citrus canker, Tungro disease of rice

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Biocontrol of insect pests Bacterial pesticides

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Genetically modified food

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Bio war, Genetically Modified Organisms (GMO) in biological warfare

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Biopiracy, Bioresources, Biomolecules, Biopatent, Biotechnology

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Sustainable agriculture

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Medicinal plants including microbes

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Commonly Available Medicinal Plants

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Microbes in medicine

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Economic importance of Food plant Rice

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Oil plant Groundnut Economic importance

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Fibre plant – Cotton Economic importance

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Fibre plant – Cotton

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Many members of Malvaceae yield fibres. Gossypium barbadense
(Egyptian cotton) and G. hirsutum are some examples for fibre plants.

The seed coat of cotton seeds produce fibres on their external surface. So, it is called as surface fibre.

Almost the entire textile industry depends on this fibre. Cotton is
used in stuffing the pillows and cushions.

It is also used in making rubber tyres, carpets, blankets and cordages are made from cotton.

Economic importance

• It is a cash crop.
• It gives three important products: fibre, food and cattle feed.
• Lint fibre is for clothing which is very much useful in the textile
  industries.
• Seed is used for extracting oil. This is also used as vanaspathi.
• Cotton flour prepared from the seed is used for bread and biscuit
  making.
• Cotton seed cake is used as a good organic manure.
• Fatty acids obtained from oil is used in the preparation of insecticide,
  fungicidies and plastics, etc.

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Plant physiology – photosynthesis and its significance

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BIOLOGY IN HUMAN WELFARE Introduction & Food production

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Aims of plant breeding

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Aspects of plant breeding and Types

---

Hybridization in plant breeding

---

Polyploid breeding, Mutation breeding, Breeding for disease resistance

---

Genetic engineering, Improved varieties, Role of biofertilizers

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Green manuring, Mycorrhiza as biofertilizer

---

Benefits from biofertilizers

---

Crop diseases and their control, Rice – Oryza sativa

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Groundnut or peanut – Arachis hypogea

---

Citrus canker, Tungro disease of rice

---

Biocontrol of insect pests Bacterial pesticides

---

Genetically modified food

---

Bio war, Genetically Modified Organisms (GMO) in biological warfare

---

Biopiracy, Bioresources, Biomolecules, Biopatent, Biotechnology

---

Sustainable agriculture

---

Medicinal plants including microbes

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Commonly Available Medicinal Plants

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Microbes in medicine

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Economic importance of Food plant Rice

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Oil plant Groundnut Economic importance

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Timber yielding plant Teak Economic importance

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Oil plant – Groundnut

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Its binomial is Arachis hypogea. It belongs to Fabaceae. It is an
annual. The word groundnut derives its name from the fact that its fruits ripe beneath the ground.

The roasted seeds are edible. Oil is extracted from the seeds and used as fine cooking medium.

Vegetable ghee (peanut butter) is also prepared from this oil. The oil cake is fed to the livestock. It is rich in fatty acids and proteins.

Economic importance

• Ground nut oil is one of the important edible oils. It is extensively used in cookery as a salad oil. It is used for the manufacture of vanaspathi.
• Groundnut kernel is rich and cheap source of vegetable protein.
  Kernels are eaten, fried and salted and added to a number of dishes.
• Peanut butter is prepared by grinding roasted and blanched kernels.
  It is nutritious.
• Groundnut oil is used to a limited extent in soap making.
• Oil is used as illuminant, lubricant.
• Oil cake is used as animal feed and organic manure.
• Groundnut shell is used in the manufacture of activated carbon.
• The groundnut cake is a good cattle feed. The plant after removing
  the pod, both dried and fresh is a good cattle feed.

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Plant physiology – photosynthesis and its significance

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BIOLOGY IN HUMAN WELFARE Introduction & Food production

---

Aims of plant breeding

---

Aspects of plant breeding and Types

---

Hybridization in plant breeding

---

Polyploid breeding, Mutation breeding, Breeding for disease resistance

---

Genetic engineering, Improved varieties, Role of biofertilizers

---

Green manuring, Mycorrhiza as biofertilizer

---

Benefits from biofertilizers

---

Crop diseases and their control, Rice – Oryza sativa

---

Groundnut or peanut – Arachis hypogea

---

Citrus canker, Tungro disease of rice

---

Biocontrol of insect pests Bacterial pesticides

---

Genetically modified food

---

Bio war, Genetically Modified Organisms (GMO) in biological warfare

---

Biopiracy, Bioresources, Biomolecules, Biopatent, Biotechnology

---

Sustainable agriculture

---

Medicinal plants including microbes

---

Commonly Available Medicinal Plants

---

Microbes in medicine

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Economic importance of Food plant Rice

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Fibre plant – Cotton Economic importance

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Timber yielding plant Teak Economic importance

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Economic importance of food plant rice

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Many plants are economically important and useful to mankind in
several ways. Based on their utility, they are broadly classified as food plants, fibre plants, oil plants and timber plants. Now, we will discuss some of the economically important plants for each category.

Food plant Rice

Its binomial is Oryza sativa. It belongs to Poaceae. It is the most
important cereal of tropical climate. This plant is an annual grass.

The inflorescence is panicle containing a number of branches, each terminating in a single grain. IR – 8, ponni, kannagi, kavery, ganga, etc. are some of the recent varieties cultivated in India.

Food plant Rice is the chief source of carbohydrates. Polished rice is less nutritive.

Straw is used as livestock feed. In Japan, alcoholic beverages are also distilled from the grains of rice.

Recently, from the husk of paddy, a cooking (rice bran oil) oil is extracted. Now, bio-diesel is obtained from rice bran oil.

Rice is the major food of half of the world’s population. Particularly
in the eastern hemisphere it is the staple food.

Rice cultivation is the onlysource of income for majority of people in our country. The uses of rice are many.

Economic importance

• Parched rice (pori) is crisp to eat. It is sold either salted or unsalted.
• The flattened parboiled rice is known as flaked rice. Like corn flakes, it is a very good break fast food. Flaked rice is also used for preparing different kinds of food items.
• Sake is an important alcoholic beverage in Japan. Sake is prepared
  by the fermentation of rice.
• Bran is an important by-product of rice milling industry. It is used as
  a cattle feed.
• Bran oil is extracted either by expression in a hydraulic press or
  extra-ction with solvents. Bran oil is used as edible oil and for
  preparation of vanaspathi, making soaps. It is also used in the textile industry, leather industry.
• Bran wax is a by-product in bran-oil extraction. It is used in chocolate industry and in the manufacture of lip-sticks.
• Paddy husk is used as fuel, in brick kilns. It is also used in brick
  making.
• Straw is used as cattle feed, in the manufacture of straw-boards and
  for making hats, ropes, mats, etc.

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Other links 

Plant physiology – photosynthesis and its significance

---

BIOLOGY IN HUMAN WELFARE Introduction & Food production

---

Aims of plant breeding

---

Aspects of plant breeding and Types

---

Hybridization in plant breeding

---

Polyploid breeding, Mutation breeding, Breeding for disease resistance

---

Genetic engineering, Improved varieties, Role of biofertilizers

---

Green manuring, Mycorrhiza as biofertilizer

---

Benefits from biofertilizers

---

Crop diseases and their control, Rice – Oryza sativa

---

Groundnut or peanut – Arachis hypogea

---

Citrus canker, Tungro disease of rice

---

Biocontrol of insect pests Bacterial pesticides

---

Genetically modified food

---

Bio war, Genetically Modified Organisms (GMO) in biological warfare

---

Biopiracy, Bioresources, Biomolecules, Biopatent, Biotechnology

---

Sustainable agriculture

---

Medicinal plants including microbes

---

Commonly Available Medicinal Plants

---

Microbes in medicine

---

Oil plant Groundnut Economic importance

---

Fibre plant – Cotton Economic importance

---

Timber yielding plant Teak Economic importance

---

Microbes in medicine

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Microbes like bacteria and fungi produce antibiotics. The substance
produced by a living organism, which inhibits the growth and metabolic activities of pathogenic organisms (mostly bacteria) without affecting the metabolism of host is called an antibiotic.

Penicillin, streptomycin, aureomycin and chloromycetin are some of the examples for antibiotics.

Penicillin is a well known antibiotic obtained from the blue green mold called Penicillium notatum. When it is grown in culture medium, the mycelium excretes an antibiotic substance called penicillin.

The crude penicillin is recovered, purified and dehydrated. It is effective against gram-positive bacteria like Pneumonia bacteria.

Streptomycin is obtained from the filamentous bacterium, Streptomyces griseus, an actinomycetes.

It cures urinary infections, tuberculosis, meningitis and pneumonia. Aureomycin mis obtained from actinomycetes, Streptomyces aureofaciens.

It is used as a medicine in the osteomyelitis, whooping cough and eye infections.

Chloromycetin is obtained from the actinomycete, Streptomyces
venezuelae. It kills bacillus form of bacteria and cures typhoid fever.
Aspergillus fumigatus produces antibiotic which is used against typhoid and dysentery.

Other group of microorganism like bacteria is also known
to produce many antibiotics. Bacillus subtilis produces 60 different
antibiotics.

Bacitracin is an antibiotic obtained from Bacillus licheniformis
and it is used to treat syphilis. It is useful in the control of sugar for
persons suffering from diabetes.

Through genetic manipulation, and introduction of human gene for insulin production, the bacterium E. coli is articulated to produce human insulin called “humulin”.

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Other links 

Plant physiology – photosynthesis and its significance

---

BIOLOGY IN HUMAN WELFARE Introduction & Food production

---

Aims of plant breeding

---

Aspects of plant breeding and Types

---

Hybridization in plant breeding

---

Polyploid breeding, Mutation breeding, Breeding for disease resistance

---

Genetic engineering, Improved varieties, Role of biofertilizers

---

Green manuring, Mycorrhiza as biofertilizer

---

Benefits from biofertilizers

---

Crop diseases and their control, Rice – Oryza sativa

---

Groundnut or peanut – Arachis hypogea

---

Citrus canker, Tungro disease of rice

---

Biocontrol of insect pests Bacterial pesticides

---

Genetically modified food

---

Bio war, Genetically Modified Organisms (GMO) in biological warfare

---

Biopiracy, Bioresources, Biomolecules, Biopatent, Biotechnology

---

Sustainable agriculture

---

Medicinal plants including microbes

---

Commonly Available Medicinal Plants

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Economic importance of Food plant Rice

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Oil plant Groundnut Economic importance

---

Fibre plant – Cotton Economic importance

---

Timber yielding plant Teak Economic importance

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COMMONLY AVAILABLE MEDICINAL PLANTS

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1. Acalypha indica

It belongs to Euphorbiaceae. The vernacular name of A. indica in
tamil is kuppaimeni, poonamayakki and its trade name is Indian Acalypha.

It is a common herb growing upto 75 cm tall with ovate leaves. Flowersare green, unisexual found in catkin inflorescence.

The paste obtained from the leaves of this plant is applied to burns.
The juice extracted from the leaves, mixed with lime and applied on skin to cure diseases caused by ringworms.

Fresh juice of leaves mixed with oil and salt is used for Rheumatoid arthritis and to cure scabies. Powdered leaves are used to cure bedsores and infected wounds.

The active medicinal compounds like Acalyphine and Triacetoneamine are extracted from this plant. They contain cyanogenic glucoside and alkaloids.

2. Aegle marmelos

It belongs to Rutaceae. The vernacular name of A. marmelos in
tamil, is vilvam. It’s trade name is baer fruit. It is an aromatic tree
growing 6 to 7.5 metres tall with long branches. Bark is grey with peeling type.

Leaves are trifoliate or pentafoliate. Leaflets are ovate. Flowers
are sweet scented with greenish white in colour and are borne on axillary panicles. Marmelosin, coumarin and triterpenoids are responsible for medicinal activity.

The unripe fruit is used to treat problems of stomach indigestion. It
kills intestinal parasites. It is used also to cure chronic diarrhoea and
dysentery. It is used as a tonic for the betterment of heart and brain.

3. Cissus quadrangularis

It belongs to Vitaceae. The vernacular name of C. quadrangularis in
tamil is as pirandai and its trade name is ‘Hadjor’ – bone joiner. It is a common shrub with tendrils. Its stem is angular, winged and contracted at nodes.

Leaves are simple, ovate or kidney shaped and thick leathery.
Coiled tendrils are found opposite to the leaves. Steroids like prescene and tetracyclic triterpenoids are the active chemicals present in this plant.

The paste obtained from the powdered stem and root of this plant is
used in bone fractures. Whole plant is useful to treat asthma and stomach troubles.

Stem is useful in the treatment of piles and its juice is used to
treat bleeding of nose.

4. Mimosa pudica

It belongs to Mimosaceae. The vernacular name of M. pudica in
tamil is ‘Thottal chinungi or Thottal surungi’. Its common english name is Touch-Me-Not plant.

It is a small herb with prickles which are erect or curved. Leaflets are arranged in two rows containing 15 to 20 pairs. Leaves are sensitive to touch. Flowers are pink and found in axillary heads.

A decoction of the root obtained from this plant is used to relieve
asthma and diarrhoea. This plant is also useful for curing piles, minor skin wounds and whooping cough. Mimosine, an alkaloid is extracted from this plant.

5. Solanum nigrum

It belongs to Solanaceae. The vernacular name of S. nigrum in tamil
is manithakkali or manathakkali. Its trade name is black night shade. It is an annual, erect, much branched and unarmed herb growing upto one metre tall. Leaves are ovate without hairs.

Flowers white borne on extra axillary cymes. Fruits are globose and black coloured berry. The extract of this herb is effective in the treatment of liver disorders like cirrhosis of liver.

This plant also cures fever, dysentery and promotes urination. Active medicinal compounds like solanin and saponin are
extracted from this plant.

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Other links 

Plant physiology – photosynthesis and its significance

---

BIOLOGY IN HUMAN WELFARE Introduction & Food production

---

Aims of plant breeding

---

Aspects of plant breeding and Types

---

Hybridization in plant breeding

---

Polyploid breeding, Mutation breeding, Breeding for disease resistance

---

Genetic engineering, Improved varieties, Role of biofertilizers

---

Green manuring, Mycorrhiza as biofertilizer

---

Benefits from biofertilizers

---

Crop diseases and their control, Rice – Oryza sativa

---

Groundnut or peanut – Arachis hypogea

---

Citrus canker, Tungro disease of rice

---

Biocontrol of insect pests Bacterial pesticides

---

Genetically modified food

---

Bio war, Genetically Modified Organisms (GMO) in biological warfare

---

Biopiracy, Bioresources, Biomolecules, Biopatent, Biotechnology

---

Sustainable agriculture

---

Medicinal plants including microbes

---

Microbes in medicine

---

Economic importance of Food plant Rice

---

Oil plant Groundnut Economic importance

---

Fibre plant – Cotton Economic importance

---

Timber yielding plant Teak Economic importance

---

Medicinal plants including microbes

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India is endowed with a rich wealth of medicinal plants. From earliest
times mankind has used hundreds of medicinal-plants in an attempt to cure diseases and relieve physical sufferings.

They derived this knowledge as a result of trial and error. Medicinal properties of plants have been mentioned even in the oldest “Rig Veda”. Medicinal plants are becoming popular throughout the developed world, as people want to treat illness.

It is estimated that around 70,000 plant species, from lichens to tall
trees, have been used as medicinal plants. 500 plants have been studied in detail.

According to WHO about 25 per cent of prescribed human medicines
are derived from plants. India accounts for nearly 1,100 species used in different systems of medicines like Ayurveda, Siddha, Unani, etc. Out of these, 600 to 700 species are used much in the country.

But 95 per cent of medicinal plants are obtained from wild sources and they are not cultivated now.

Now, efforts are being made to introduce many of these useful plants
to farmers.

Agronomic practices have been developed for growing poppy,
isobgol, cincona, belladona, ergot, etc.

Medicinal plants have curative properties due to presence of various complex chemical substances in different composition like alkaloids, glycosides, corticosteroids, essential oils, etc.

Nowadays, these medicinally valuable compounds obtained
from the medicinal plants are called ”biomedicines”.

Some of the important medicinal-plants and their products are

Morphine, the strongest pain killer obtained from Opium poppy –
Papaver somniferum.

Quinine, antimalarial drug which controls malarial fever is derived
from Cinchona calisaya and C. officinalis.

Digoxin, used to treat heart diseases is obtained from the plant
Digitalis.

Ephedrine, used to treat cough is extracted from the plant Ephedra
sinica.

Mental and physical stress relaxing drug is obtained from the plant
ginseng – Panax ginseng.

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Other links 

Plant physiology – photosynthesis and its significance

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BIOLOGY IN HUMAN WELFARE Introduction & Food production

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Aims of plant breeding

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Aspects of plant breeding and Types

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Hybridization in plant breeding

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Polyploid breeding, Mutation breeding, Breeding for disease resistance

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Genetic engineering, Improved varieties, Role of biofertilizers

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Green manuring, Mycorrhiza as biofertilizer

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Benefits from biofertilizers

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Crop diseases and their control, Rice – Oryza sativa

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Groundnut or peanut – Arachis hypogea

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Citrus canker, Tungro disease of rice

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Biocontrol of insect pests Bacterial pesticides

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Genetically modified food

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Bio war, Genetically Modified Organisms (GMO) in biological warfare

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Biopiracy, Bioresources, Biomolecules, Biopatent, Biotechnology

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Sustainable agriculture

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Commonly Available Medicinal Plants

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Microbes in medicine

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Economic importance of Food plant Rice

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Oil plant Groundnut Economic importance

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Fibre plant – Cotton Economic importance

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Timber yielding plant Teak Economic importance

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