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Friday, February 27, 2009
Intellectual Property Rights [IPR] as Career
IPR is “INTELLECTUAL PROPERTY RIGHTS”.
These are legal rights which are granted for creation of the minds.
If you have created something eg:song,poem or a book or even a new invention in biotechnology which has a commercial application or value,you are entitled to get rights for it.
Intellectual property or creation of mind or intellectual are like property that have commercial value.
They can be bought and sold just like conventional property.
Since IPR can be bought and sold just like property,we use the term “intellectual property”
WHAT IS THE NEED FOR IPR?
IPR are needed to reward original effort.
The main concept behind all forms of IP,be it patents or copyright or industrial design etc is that the person who has put in original effort must have rights over his creation and must get rewarded for it.
He must not be cheated.
Thus IPR lead to progress and development by ensuring rights and regulations for people who put in original effort.
BRIEF HISTORY
The first intellectual property law was passed in VENICE in 1474 which protected the investor’s interest against copying of their creation.
England soon followed the suit to grant intellectual property rights to its inventor for a limited period.
With increase in international trade intellectual property theft was on the rise.
This led the birth of Paris Convention.
Intellectual property can be broadly divided into two categories.
- Copyright.
- Industrial property.
- George Washington University
- Franklin Pierce Law Centre
- Columbia University
- Stanford University
- New York University
- National Law School
- National University Of Juridical Science
- Symbiosis Institute
- Online courses by WIPO:http://academy.wipo int
- Basic information about IPR: www.patentmatics.org and www.ipindai.nic.in
JOB PROSPECT
IPR attorneys are integral part of in-house teams of buiseness organizations formed with the sole aim of identifying and stopping copyright infringements.
IPR attorneys are also being actively employed by a whole range of organizations like Specialty Law Firms,Government and self supported think tanks,Law Enforcing Bodies and Universities.
LAW FIRMS
Most of the law firms especially in developed and emerging economics like the US,India and China has specilaised divisions that cater to litigations concerning of infringement of intellectual properties.
In US there are law firms that specialize in intellectual property law.
GOVERNMENT AGENCIES AND THINK TANK
These are one of the prolific employes of IPR attorneys.
One of the most obvious agencies is the patent and copyright office of any country.
Other departments that employ IP attorneys are defence,information technology,justice and commerce.
UNIVERSITIES AND RESEARCH ORGANIZATIONS
Universities take up projects.
These projects involve various technologies.
Thus various universities have an in-house of IPR lawyers that protect their interests.
IPR JOBS IN INDIA
- Kirloskar Brothers Limited.
- Maha India.
- Robert Bosch Engineering.
- General Physics Corporation
- Harbinger Systems.
- Heaque Creations.
- United Health Group.
The category for IPRs most important for researchers is patents.
Knowledge of IPRs is important for researchers in many ways.
Prevents duplication of work.
Helps researchers to focus on commercially relevant research.
Prevents exploitation of workers.
Helps in revenue generation.
Prevents infringements and helps avoid litigation.
DOES ONE NEED A LEGAL BACKGROUND FOR MAKING USE OF IPRs?
No, one Required to have fundamentals cleared.
Whether the work your doing is really original.
Is it infringing upon somebody’s rights or not?
What is the global technology status of the research work your about to start?
Whether what you have achieved in the lab is patentable or not?
You need assistance of lawyers and legal experts.
CAREER OPPORTUNITIES FOR BIOTECHNOLOGISTS
Knowledge of IPR is important for biotech industries and teaching institutes.
Basic courses of WIPO:-preference in interviews and placements.
Sought by patent attorney firms and consultancy firms.
R and D production.
HOW IT HELPS IN R & D
Networking with R & D people and finding out whether their work is patentable or not.
Search patent database.
Guiding your R & D colleagues.
Indentification of new and emerging technologies.
HOW IT HELPS IN ATTORNEY FIRMS
Filing of biotechnology patents requires a sound technical knowledge.
Thus most firms are hiring M.Sc/Phd candidates having biotechnology background.
IPR AND TECHNOLOGY MANAGEMENTS
Patents filed and not commercialized are a tremendous loss of time ,money and effort.
Once rights over the work are created, inventors can freely contact and interact with industry professionals,disclosing details of their work without any fear that their work will be copied.
CAREER OPPORTUNITIES IN TECHNOLOGY MANAGEMENT
Demand in abroad.
Hybrid degrees.
It’s a different career.
Some Facts IPR
It’s a broad field.
Most important legal field in United States.
Most demanded specialty of intellectual property law is patent law.
This is because they are few and the demand is more.
Tuesday, February 24, 2009
Plant Growth Regulators In Agriculture
Plant Growth Regulators:
Plant hormones (also known as plant growth regulators (PGRs) and phytohormones) are chemicals that regulate a plant's growth. Plant hormones on the other hand, are not like animal hormones, they are often not transported to other parts of the plant and production is not limited to specific locations. Plants lack tissues or organs specifically for the production of hormones; unlike animals, plants lack glands that produce and secrete hormones to be moved around the body. Plant hormones shape the plant, effecting seed growth, time of flowering, the sex of flowers, its longevity, senescence of leaves and fruits, they affect which tissues grow up and which grow downward, leaf formation and stem growth, fruit development and ripening, and even plant death. Hormones are vital to plant growth and lacking them plants would be mostly a mass of undifferentiated cells.
Hormones:
In plants, many behavioral patterns and functions are controlled by hormones. These are “chemical messengers” influencing many patterns of plant development.
¡ Plant hormones – a natural substance (produced by plant) that acts to control plant activities. Chemical messengers.
¡ Growth Regulators
¡ Plant growth regulators – include plant hormones (natural & synthetic), but also include non-nutrient chemicals not found naturally in plants that when applied to plants, influence their growth and development.
¡ 5 recognized groups of natural plant hormones and growth regulators.
1. Auxins
2. Gibberellins
3. Cytokinins
4. Ethylene
5. Abscisic acid
Cortesy: Amit Bhaskar
Sunday, February 22, 2009
Secondary Metabolite Production In Plants
Secondary Metabolite Production
Secondary metabolites are chemical compounds and the chemical compounds produced by plants are collectively called as phytochemicals.Secondary metabolites are those chemical compounds that do not participate in metabolism of plants. But these compounds are involved in disease resistance (from fungus, bacteria, viral, and pests), for pollination and to compact in extreme conditions of stress. The stress may be biotic or abiotic [Drought, Cold, Temparature, etc.].some of the secondary metabolites are Alkaloids, Steroids, terpenoids, essential oils, flavours, fragrance, colours & pigments.
Application of secondary metabolites
Secondary metabolites are widely used in many industrial products, some of them are
- Ø Nuetraceuticals
- Ø Textile Industry
- Ø Cosmoceuticals
- Ø Pharmaceuticals
- Ø Perfume Industry, etc.
Terpenoids, Steroids and steroids are used in 25% of the prescribed drugs, and almost all cancer drugs are sourced from plants. Colours and fragrances are used in textile and food industry. Some of the plant species that produce the secondary metabolites of great industrial importance. Like Taxas burgata which produce Taxol is used in cancer treatment, all parts of the plant has the capacity to produce this compound.Coleus forskohli which produces the compound Forskohlin is used in treatment for Glaucoma, only roots are capable of producing the secondary metabolite in this plant. Lithospermum erythrorhizon which produce Shinkonin.
Production of secondary metabolites
The process of invitro culture of cells for the large scale production of secondary metabolite is complex, and involves the following aspects
- Ø Developing Mother Culture
- Ø Selection of cell lines for high yield of secondary metabolites.
- Ø Large scale cultivation of plant cells
- Ø Medium composition and effect of nutrients
- Ø Elicitor induced production of secondary metabolites
- Ø Effect of environmental factors
- Ø Biotransformation using plant cell culture
- Ø Secondary metabolites and analysis.
The culture, which is produced, first is called mother culture. Different cultures has been developed like callus, multiple shoots, roots, etc among these which of the culture can be produced easily, will be selected for further culturing.
The callus can be developed from explant or from a mother culture, which is already developed. Different types of callus can be obtained like Nodular Callus, Friable Callus Pigment Callus, Embryonic Callus, etc. among those friable callus (loosely packed callus) is preferred. If friable callus is not producing it can be induced by certain treatments. When the friable callus is put in liquid medium and kept in shaker the cells of the callus will get dissociated. Usually 75ml of the media is taken in 250ml flask, the optimum inoculating density is 5mg / 75ml, the pH of the medium should be 5.6.the flask is kept in a Gyratory Shaker at 120 rpm, which is for the aeration of the medium. The speed varies depending on the plant species.
Sub Culturing:
Sub culturing can be done when the cells are in the exponential stage, the stage of development can be identified by growth pattern studies. The culturing can be done by batch culture or by continous culture. One of the method is 5ml of inoculum from the suspension [75ml] is transferred 70ml of fresh medium. Like this way 15 or more flasks of culture can be produced. Another method is that, divide the media equally into two parts and add the fresh media to make-up to 75ml and this process is continued.
For identification of the stage and analysis of the product growth pattern studies are very much important. Growth study is done for 25days form the starting. For studying growth different methods (Optical Density, Dry weight, Cell counting) can be used. By this we can know the Packed Cell Volume (PCV) along with that content analysis also can be done so we will get a clear idea that on particular day at a particular stage of growth the cell is producing the secondary metabolite. Moreover the target of the product also can be known,ie. Whether it is produced Intracellular or Extracellular.
Callus Culture |
The purpose of tissue culture is to produce high amount of secondary metabolite, but in general majority of the callus and suspension cultures produce less quantity of secondary metabolites. The reason for this is mainly due to the lack of fully differentiated cells in the cultures. There are some techniques ultimately useful for the separation of producers and non-producers. The techniques employed for this are cell cloning, Visual and Chemical analysis and selection for resistance.
This is a simple procedure and involves the growth of single cells (taken from suspension culture) in a suitable medium. Each cell population is then screened for secondary metabolite formation. The cells with high ability are selected and maintained by subcloning.
Aggregate Cell Cloning:
Bioreactors for the Production of Secondary metabolites
- Batch Bioreactors
- Continuous Bioreactors
- Multistage Bioreactors
- Airlift Bioreactors
- Stirred Tank Bioreactors
- Adequate and Continous Oxygen Supply
- Minimal generation of hydrodynamic stresses due to aeration and agitation.
Plant cells can be made immobile or immovable and used in culture systems. The cells are physically immobilized by entrapment. Besides individual cells it is possible to immobilize aggregate cells or even calluses. Homogenous cell suspensions are more suitable for immobilization.
Surface immobilized plant cell (SIPC) technique efficiently retains the cells and allow them to grow at a higher rate. When the cells are immobilized there is a better cell-cell contact, and the cells are protected from high shear and stresses. All these helps in the maximal production of secondary metabolite.
Entrapment of cells in nets or foams: Polyurethane or nets with various pore sizes are used.The actively growing plant cells in suspension can be immobilized on these foams.The cells divide within the compartments of foam and foam aggregates.
For the production of hairy root cultures, the explant material is inoculated with pathogenic bacterium, Agrobacterium rhizogenes. The organism contains root-inducing (Ri) plasmid that causes genetic transformation of plant tissues, which finally results in the hairy root cultures. Hairy roots produced by plant tissues have metabolite features similar to that of normal tissues.
Factors affecting Secondary Metabolite production
There are various factors affecting Secondary metabolite production, some of the major factors includes
- Light
- Incubation Temperature
- pH of the medium
- Aeration of the culture, etc
The conversion of one chemical into another (ie, a substrate into a final product) by using biological systems (ie, cell suspensions) as biocatalysts is regarded as Biotransformation or bioconversion the biocatalyst may be free or immobilized, and the process of Biotransformation involve one or more enzymes.
Male Sterility in Plants
Plant that do not produce viable, functional pollen grains.
Male Sterility: An inability to produce or to release functional pollen as a result of failure of formation or development of functional stamens, microspores or gametes
Types of Sterility
Three types of sterility:
- “Pollen sterility” in which male sterile individuals differ from normal only in the absence or extreme scarcity of functional pollen grains (the most common and the only one that has played a major role in plant breeding).
- “Structural or staminal male sterility” in which male flowers or stamen are malformed and non functional or completely absent
- “Functional male sterility” in which perfectly good and viable pollen is trapped in indehiscent anther and thus prevented from functioning
Classification of Male Sterility
Based on its inheritance or origin:
1. Cytoplasmic male sterility (CMS) = sterile cytoplasm (S)
Male sterility comes about as a result of the combined action of nuclear genes and genic or structural changes in the cytoplasmic organellar genome
maternally inherited
2. Nuclear male sterility (NMS) = Genic, genetic, mendelian
Male sterility is governed solely by one or more nuclear genes
Nuclear inherited
3. Non genetic, chemically induced male sterility
Application of specific chemical (gametocides or chemical hybridizing agents)
Stamen (anther and filament) and pollen grains are affected
It is divided into:
a. Autoplasmic
CMS has arisen within a species as a result of spontaneous
mutational changes in the cytoplasm, most likely in the
mitochondrial genome
b. Alloplasmic
CMS has arisen from intergeneric, interpecific or occasionally
intraspecific crosses and where the male sterility can be
interpreted as being due to incompatibility or poor co-operation
between nuclear genome of one species and the organellar
genome another
CMS can be a result of interspecific protoplast fusion
Cytoplasmic Male Sterility
Origins:
1. Intergeneric crosses
2. Interspecific crosses
3. Intraspecific crosses
4. Mutagens (EMS, EtBr)
5. Antibiotic (streptomycin and Mitomycin)
6. Spontaneus
CMS Mechanism of Action
1. Abnormal behavior of the tapetum in the anther
2. Genetic determinant of CMS reside in mitochondria
3. Nuclear gene control the expression of CMS
CMS Limitations
1. Pleiotropic negative effect of the CMS on agronomic quality performance of plants in the CMS cytoplasm
2. Enhanced disease susceptibility
3. Complex and environmentally unstable maintenance of male sterility and/or male fertility restoration
4. Inability to produce commercial quantities of hybrid seed economically because of poor floral characteristic of cross pollination
Utilization of CMS
1. It provides a possible mechanism of pollination control in plants to permit the easy production of commercial quantities of hybrid seeds
2. It consists of a male sterile line (the A-line), an isogenic maintainer line (The B line), and if necessary also restore line (the R-line)
3. A lines are developed by back-crossing selected B-lines to a CMS A-line for 4 – 6 times to generate a new A-line
4. B and R-lines are developed by similar back cross procedures using a CMS R-line as female in the original cross and a new line as the recurrent parent in 4 – 6 backcrosses
Nuclear Male Sterility [NMS]
1. Originated through spontaneous mutation or mutation by ionizing radiation and chemical mutagens such as ethyl methane sulphonate (EMS) and ethyl imine (EI) or by genetic engineering, protoplast fusion, T-DNA transposon tagging and affecting the synthesis of flavonoids
2. can probably be found in all diploid species
3. Usually controlled by mutations in genes in the single recessive genes affect stamen and pollen development, but it can be regulated also by dominant genes
Methods of Inducing Male Sterility
1. Through Chemical Agents
2. Through Recombinant DNA (rDNA) Technology
Chemical Agents Used
1. Plant hormones/hormones antagonists
a. auxins and auxin antagonists (NAA, IBA, 2,4-D, TIBA, MH)
b. Gibberellins and antagonist (GA3, GA4+7, CCC: 2-chloroethyl-trimethyl ammonium chloride)
c. Abscisic acid
2. Other substances
a. LY195259
b. TD1123
Recombinant Methods
Targetting the expression of a gene encoding a cytotoxin by placing it under the control of an ather specific promoter (Promoter of TA29 gene)
Expression of gene encoding ribonuclease (chemical synthesized RNAse-T1 from Aspergillus oryzae and natural gene barnase from Bacillus amyloliquefaciens)
RNAse production leads to precocious degeneration of tapetum cells, the arrest of microspore development and male sterility. It is a dominant nuclear encoded or genetic male sterile (GMS), although the majority of endogenous GMS is recessive
Fertility Restoration
Restorer gene (RF) must be devised that can suppress the action of the male sterility gene (Barstar)
a specific inhibitor of barnase
Also derived from B. amyloliquefacien Served to protect the bacterium from its own RNAse activity by forming a diffusion-dependent, extreemely one to one complex which is devoid of residual RNase activity
The use of similar promoter to ensure that it would be activated in tapetal cells at the same time and to maximize the chance that barstar molecule would accumulate in amounts at least equal to barnase
Inhibiting the male sterility gene by antisense. But in the cases where the male sterility gene is itself antisense, designing a restorer counterpart is more problematic
Strategies to Propagate Male-Sterile Plant
1. Selection by herbicide application
2. Inducible sterility
3. Inducible fertility
4. Two-component system
Tuesday, February 10, 2009
Tuberculosis : "Mammalian Tubercle Bacilli"
Monday, February 9, 2009
Polymerase Chain Reaction: Copying DNA is Copyright Protected???
Polymerase chain reaction (PCR) enables researchers to produce millions of copies of a specific DNA sequence in approximately two hours. This automated process bypasses the need to use bacteria for amplifying DNA.
The four nucleotide bases, the building blocks of every piece of DNA, are represented by the letters A, C, G, and T, which stand for their chemical names: adenine, cytosine, guanine, and thymine. The A on one strand always pairs with the T on the other, whereas C always pairs with G. The two strands are said to be complementary to each other.
Biofertilizer: Eco-Friendly
Image Source: Google Images
The setup is made to treat liquid as well as solid wastes.Rejuvenation of Soil & healthy Plant & soil relationship. Conversion of Bio-waste into organic bio-fertilizers.Unique microbial and vermiculture conversion technology.7,000 MT of bio-fertilizers to be produced per annum.Pioneering work to develop an unique process.
Gene Therapy : A New Approach
Ethical Issues on GM Crops
Saturday, February 7, 2009
Stem Cells: As regenerative Medicine
Research on stem cells is advancing knowledge about how an organism develops from a single cell and how healthy cells replace damaged cells in adult organisms. This promising area of science is also leading scientists to investigate the possibility of cell-based therapies to treat disease, which is often referred to as regenerative or reparative medicine.
Stem cells are one of the most fascinating areas of biology today. But like many expanding fields of scientific inquiry, research on stem cells raises s
Stem Cells
Image source: Google Images
Nanotechology: Introduction, Types & Nanoparticles
The term "nanotechnology" has evolved over the years via terminology drift to mean "anything smaller than microtechnology," such as nano powders, and other things that are nanoscale in size, but not referring to mechanisms that have been purposefully built from nanoscale components
Source:
http://www.nanotech-now.com/introduction.htm
Image source: google images
Nanotechnology Basics
Coined as "nano-technology" in a 1974 paper by Norio Taniguchi at the University of Tokyo, and encompassing a multitude of rapidly emerging technologies, based upon the scaling down of existing technologies to the next level of precision and miniaturization. Taniguchi approached nanotechnology from the 'top-down' standpoint, from the viewpoint of a precision engineer.
Source:
http://www.nanotech-now.com/basics.htm
Types: Nanoparticles
Extensive libraries of nanoparticles, composed of an assortment of different sizes, shapes, and materials, and with various chemical and surface properties, have already been constructed. The field of nanotechnology is under constant and rapid growth and new additions continue to suppliment these libraries. The classes of nanoparticles listed below are a
Source:
http://biotech.about.com/od/nanotechnology/a/typesnanopart.htm
Friday, February 6, 2009
Transgenic Sweet Potatoes
Image from Google images
Source:
http://www.ingentaconnect.com/content/els/01689452/1998/00000139/00000002/art00179;jsessionid=36settq10h8gu.alexandra
Sweet potato is a major crop that feeds millions of people in the developing world. It is especially popular among farmers with limited resources, and produces more biomass and nutrients per hectare than any other food crop in the world. New biotechnological approaches may enable scientists to rapidly develop superior, disease and pest resistant cultivars.
Sweet potato (Ipomoea batatas L.) is adaptable to a broad range of agroecological conditions and fits in lowinput agriculture. It is highly productive even under adverse farming conditions. Sweet potato is grown in more than 100 countries as a valuable source of food, animal feed and industrial raw material. It is a staple crop in many SouthEast Asian and African countries.
Source:
http://www.biotech-monitor.nl/1811.htm
Golden Rice -
Image from Google images
Reference:
Fowler, Plant Biotechnology
Transgenic Plants for Crop Improvement
Source:Journal of Experimental Botany
http://jxb.oxfordjournals.org/cgi/content/full/51/suppl_1/487
Plant Hormones and Growth Regulators
image source: google images
Palnt Grorth Regulators are responsible for the growth and development of the plants..
What is a hormone?
As plants grow their genotype is expressed in the phenotype which is modified by the environmental conditions that they experience. Somehow the rates of growth and differentiation of cells in different parts of the plant are coordinated in response to these inputs.
Suggested Books for this Topic:
Bhan (1998), Tissue Culture Mittal Publications, New Delhi
Gupta P.K, Elements of Biotechnology, Rastogi & Co.
Dr. U. Satynarayana, Biotechnology
Media Preparation Plant Tissue Culture
Source:
http://www.molecular-plant-biotechnology.info/plant-tissue-culture/media-preparation.htm
*above image is from Google Images
Suggested Books for this Topic:
Bhan (1998), Tissue Culture Mittal Publications, New Delhi
Gupta P.K, Elements of Biotechnology, Rastogi & Co.
Dr. U. Satynarayana, Biotechnology
Plant Tissue Cultre Media
Human Genome Project
Tuesday, February 3, 2009
Cytoplasmic Male Sterility in Plants
Plants with male sterility don’t produce functional / viable pollen grains.
Male Sterility is of two types:
Cytoplasmic Male sterility
Genic Male sterility
Advantages of Male Sterility & Its Importance in Plant Biotechnology
In palnt breeding to obtain hybrids cross pollination need to be done among selected parental lines High level of self pollination any occur especially in bisexual plants. This hampers hybrid seed production to overcome this problem and ensure crosses between the selected female and selected male, several types of pollination control need to be used.
Mannual emasculation
CMS
GMS
Self Incompatibility
male Gametocides
Use of genetically Engineered Systems for Male Sterility
Male sterility in plants may be nuclear or Cytoplasmic. Cytoplasmic male sterilityis invariably due to defective functioning of to the tapetum of the anthers. The main function of tapetum is to supply nutrients to developing pollen grains. So far 40 plant species are reported to have Cytoplasmic male sterility.
In maize there are specific nuclear genes which are called as fertility restoring genes (Rf). Rf genes restore polar fertility after crossing. In such case when male sterile plants with CMS is crossed with maize with Rf genes produce male fertile plants. Hence the defect from Mitochondrial function can be corrected by product encoded by nuclear genome of restorer maize.
Cytoplasmic male sterility is due to presence of additional DNA sequence in mitochondria designated as T-urf13, that codes for 13000 molecular weight polypeptide.
Restorer nuclear genome suppresses the synthesis of this polypeptide.CMS has become a major focus in Agriculture Biotechnology
In plant breeding two parental types are crossed to produce high yielding varities. Hybrid vigour or heterosis expressed only in F1 generation. Yield reduces rapidly with subsequent generations. Hence to cross two parental types the anthers of Female plant i.e., Seed producing plant is either removed or emasculated. This process is a labour intensive process and it is impractical. to perform on large scale.
Hence CMS lines play a role as they are genetically emasculated. These CMS lines are not capable of producing viable pollen, emasculation is not necessary to produce hybrid seeds. During hybrid seed production 3 lines of plants are maintained.
A – Line (Hybrid Seed Producing Parent) with CMS (defective mitochondrial genes) and recessive restorer genes in the nucleus.
B – Line: These are called as maintainers. This maintainers have normal(N) cytoplasmic genes but recessive restorer genes.
C- Line: Restorer Plant. They have normal cytoplasm and dominant nuclear restorer genes.
When A line is Crossed with B line
A
Both Cytoplasmic and nuclear Normal Cytoplasm but Nuclear
Male sterility.No viable pollen male sterility because of normal cytoplasm viable pollen
(Female) are produced
(Male)
Hybrid Plant
(Maintainer Plants)
No viable Pollen
Cytoplasmic Male Sterility [CMS]
Cytoplasmic Male Sterility is noticed in more than 150 species. Cytoplasmic Male Sterility is invariably due to defects in mitochondrial genome and it is exclusively maternally inherited. Female fertility is not affected by Cytoplasmic male sterility. Palnts with Cytoplasmic male sterility do produce seeds if viable pollen is provided.
To increase crop productivity, in recent years there has been the development of hybrid cultivar in a wide range of crops crosses between genetically distinct parental lines or populations give rise to progeny that exhibit heterosis or hybrid vigor. Hybrids in general are more resistant to disease and insects, less suceptible to environmental stress and yield more seed.
Inorder to do cross pollination CMS is most beneficial factor as it is not needed to emasculate the flower which is practically very difficult to perform in minute flowers.
The CMS is mainly due to defective functioning of tapetum of the anther. The main function of pollen is to supply nutrients to developing pollen grains. In nature CMS orginates because of intergenc crosses, Interspecific crosses,