In vitro pollination involves pollinating pistils or ovules that have been cultured in a nutrient medium such as Nitsch's medium. This technique can help overcome pre-fertilization barriers to hybridization between plant species. Key steps include sterilizing flower parts, collecting pollen, and applying pollen to excised pistils, ovaries, ovules, or stigmas depending on the method. Factors like culture medium, temperature, genotype, and physiological state of the explant can influence seed set. In vitro pollination has applications in plant breeding like overcoming self-incompatibility or cross-incompatibility barriers and producing haploid plants or hybrids.
Invitro culture of unpollinated ovaries and ovules represents an alternative for the production of haploid plant
First successful report on the induction of gynogenic haploid was in barley by San Noeum in 1976
Haploid plants are obtained from ovary and ovule culture of rice, wheat, maize, sunflower, tobacco, poplar, mulberry etc
Whites or MS or N6 inorganic salt medium supplement with growth substances are used
Invitro culture of unpollinated ovaries and ovules represents an alternative for the production of haploid plant
First successful report on the induction of gynogenic haploid was in barley by San Noeum in 1976
Haploid plants are obtained from ovary and ovule culture of rice, wheat, maize, sunflower, tobacco, poplar, mulberry etc
Whites or MS or N6 inorganic salt medium supplement with growth substances are used
Somaclonal Variation in Plant tissue culture - Variation in somaclones (somatic cells of plants)
Somaclonal variation # Basis of somaclonal variation # General feature of Somaclonal variations # Types and causes of somaclonal variation # Isolation procedure of somaclones via without in-vitro method and with in-vitro method with their limitations and advantages # Detection of isolated somaclonal variation # Application (with examples respectively related to crop improvement) # Advantages and disadvantages of somaclonal variations.
https://www.youtube.com/watch?v=IZwrkgADM3I
Also watch, Gametoclonal variation slides to understand, how to changes occur in gametoclones of plants.
https://www.slideshare.net/SharmasClasses/gametoclonal-variation
A process where an embryo is derived from a single somatic cell or group of somatic cells. Somatic embryos (SEs) are formed from plant cells that are not normally involved in embryo formation.
Embryos formed by somatic embryogenesis are called Embryoids.
The process was discovered for the first time in Daucas carota L. (carrot) by Steward (1958), Reinert (1959).
Artificial Seed - Definition, Types & Production ANUGYA JAISWAL
Somatic embryogenesis is expected to be the only clonal propagation system economically viable for crops currently propagated by seeds However, it would require mechanical planting of somatic embryogenesis. Although suggestions have been made to use naked embryos for large scale planting, it would be desirable to convert them into 'synthetic seeds' or 'synseeds' by encapsulating in a protective covering.
Kitto and Janick (1982, 1985a,b) selected polyoxyethylene (Polyox r) which is readily soluble in water and dries to form a thin film, does not support growth of microorganism and is non-toxic to the embryos.
Organogenesis, in plant tissue cultureKAUSHAL SAHU
Introduction
Definition
Types of organogenesis
Organogenesis through callus formation (indirect organogenesis)
Growth regulators for indirect organogenesis
Organogenesis through adventitious organ (direct organogenesis)
Growth regulators for direct organogenesis
Factor affecting the soot bud differentiation
Organogenic differentiation
Application of organogenesis
Conclusion
References
OVARY CULTURE:-
"the in-vitro culturing of ovaries in an aseptic condition from the pollinated or un-pollinated flowers, in an appropriate nutrient medium and under optimal conditions." And
OVULE CULTURE:-
"Ovule culture is an experimental system by which ovules are aseptically isolated from the ovary and are grown aseptically on chemically defined nutrient medium under controlled conditions."
Embryo culture is a laboratory method for producing plant lets from a fertilized or unfertilized embryo in invitro condition. there are several advantages are associated with the embryo culture like production of haploid plants, making distant crosses successful, sometimes aborted embryos can be rescued from a unsuccessful hybridization.
HYBRIDIZATION & HAPLOID PRODUCTION
Introduction
WIDE HYBRIDIZATION
INTER-SPECIFIC HYBRIDIZATION
Barriers to distant hybridization
Techniques to overcome barriers
Haploids and Doubled Haploids in Plant
Production of haploids and doubled haploids
a) Induction of maternal haploids
Wide hybridization
3. In vitro induction of maternal haploids – gynogenesis
Induction of paternal haploids – Androgenesis
Production of Homozygous Diploid Plants
Application of Haploids in Plant Breeding
Importance and Implications of Anther and Pollen Culture
The presentation gives overview of production of secondary metabolites using callus culture as well as tissue culture techniques. Various batch and continuous culturing process are described on the basis of secondary metabolite to be synthesised.
Somaclonal Variation in Plant tissue culture - Variation in somaclones (somatic cells of plants)
Somaclonal variation # Basis of somaclonal variation # General feature of Somaclonal variations # Types and causes of somaclonal variation # Isolation procedure of somaclones via without in-vitro method and with in-vitro method with their limitations and advantages # Detection of isolated somaclonal variation # Application (with examples respectively related to crop improvement) # Advantages and disadvantages of somaclonal variations.
https://www.youtube.com/watch?v=IZwrkgADM3I
Also watch, Gametoclonal variation slides to understand, how to changes occur in gametoclones of plants.
https://www.slideshare.net/SharmasClasses/gametoclonal-variation
A process where an embryo is derived from a single somatic cell or group of somatic cells. Somatic embryos (SEs) are formed from plant cells that are not normally involved in embryo formation.
Embryos formed by somatic embryogenesis are called Embryoids.
The process was discovered for the first time in Daucas carota L. (carrot) by Steward (1958), Reinert (1959).
Artificial Seed - Definition, Types & Production ANUGYA JAISWAL
Somatic embryogenesis is expected to be the only clonal propagation system economically viable for crops currently propagated by seeds However, it would require mechanical planting of somatic embryogenesis. Although suggestions have been made to use naked embryos for large scale planting, it would be desirable to convert them into 'synthetic seeds' or 'synseeds' by encapsulating in a protective covering.
Kitto and Janick (1982, 1985a,b) selected polyoxyethylene (Polyox r) which is readily soluble in water and dries to form a thin film, does not support growth of microorganism and is non-toxic to the embryos.
Organogenesis, in plant tissue cultureKAUSHAL SAHU
Introduction
Definition
Types of organogenesis
Organogenesis through callus formation (indirect organogenesis)
Growth regulators for indirect organogenesis
Organogenesis through adventitious organ (direct organogenesis)
Growth regulators for direct organogenesis
Factor affecting the soot bud differentiation
Organogenic differentiation
Application of organogenesis
Conclusion
References
OVARY CULTURE:-
"the in-vitro culturing of ovaries in an aseptic condition from the pollinated or un-pollinated flowers, in an appropriate nutrient medium and under optimal conditions." And
OVULE CULTURE:-
"Ovule culture is an experimental system by which ovules are aseptically isolated from the ovary and are grown aseptically on chemically defined nutrient medium under controlled conditions."
Embryo culture is a laboratory method for producing plant lets from a fertilized or unfertilized embryo in invitro condition. there are several advantages are associated with the embryo culture like production of haploid plants, making distant crosses successful, sometimes aborted embryos can be rescued from a unsuccessful hybridization.
HYBRIDIZATION & HAPLOID PRODUCTION
Introduction
WIDE HYBRIDIZATION
INTER-SPECIFIC HYBRIDIZATION
Barriers to distant hybridization
Techniques to overcome barriers
Haploids and Doubled Haploids in Plant
Production of haploids and doubled haploids
a) Induction of maternal haploids
Wide hybridization
3. In vitro induction of maternal haploids – gynogenesis
Induction of paternal haploids – Androgenesis
Production of Homozygous Diploid Plants
Application of Haploids in Plant Breeding
Importance and Implications of Anther and Pollen Culture
The presentation gives overview of production of secondary metabolites using callus culture as well as tissue culture techniques. Various batch and continuous culturing process are described on the basis of secondary metabolite to be synthesised.
‘vitro’ means glass or glassy substances.
So, ‘in vitro’ means in glass or glass tube.
Cultivation of plant tissue or other organs
on artificial media in a test tube or conical
flask is called in vitro technique.
The process of seed formation following
stigmatic pollination of cultured pistil has
been referred to as in vitro pollination and
the development of seed through in vitro
fertilization.
• Seed culture is an important technique when explants are taken from in vitro-derived plants and in propagation of orchids.
• Embryo culture represents the earliest technique to obtain viable offspring following interspecific and intergeneric hybridizations where routine fertilization failed to produce a well-defined and full-term embryo.
• Embryo rescue holds great promise not only for effecting wide crosses, but also for obtaining haploid plants as well as for shortening the breeding cycle.
INVITRO CULTURE: TECHNIQUES, APPLICATIOSNS & ACHIEVEMENTS.
INVITRO TECHNIQUES AND BIOTECHNOLOGY USE IN AGRICULTURE AND CROP IMPROVEMENT. APPLICATIONS OF VARIOUS BIOTECHNOLOGICAL TECHNIQUES AND METHODS. TISSUE CULTURE, MICROPROPAGATION, EMBRYO CULTURE, ANTHER CULTURE, POLLEN CULTURE, ENDOSPERM CULTURE, OVULE CULTURE, OVARY CULTURE, ETC.
Effects of selenium on wheat plants under drought conditionAriful Islam Sagar
Drought stress is considered to be one of the major agricultural problems around the globe. Selenium (Se) is known to reduce the severe effects of various environmental stresses in plants. Therefore, the aim of this study is to explore the physiological and biochemical modifications induced by Se supply to improve the drought tolerance potential of wheat. Experiment was designed with two water treatments {with (W) and without water (D)}, Se (S) alone and Se combined with D (S+D). Drought stress significantly inhibited the growth of wheat seedlings however Se supply increased shoot weight. Under drought stress, extra Se supply increased the antioxidant capacity, osmoprotectants of wheat seedlings through maintenance of turgor and gas exchange characteristics and enhancement in antioxidant system activity A significant decrease in growth parameters and soluble protein content was caused by the drought stress when an increase in root production, proline content, peroxidase (POD) and catalase (CAT) activity of leaf tissue occurred. Application of se significantly reduced osmotic potential which markedly improved turgor, increased transpiration rate, increases accumulation of total soluble sugars and free amino acids and antioxidant system activity which eventually improves the grain production efficiency. Additional nutrient uptake, relative water content’s, crop growth rate also affected by supplemental Se but the biomass accumulation under drought stress had no significant effect.
September on Jessore Road is a poem by Allen Ginsberg on refugees from Bangladesh Liberation war in 1971. During Bangladesh's Liberation War in 1971, the US government was an ally of Pakistan and even sent its 7th fleet to intimidate India from interfering with the events in then East Pakistan.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
3. Introduction
‘vitro’ means glass or glassy substances. So, ‘in vitro’
means in glass or glass tube.
Cultivation of plant tissue or other organs on artificial media
in a test tube or conical flask is called in vitro technique.
The process of seed formation following stigmatic
pollination of cultured pistil has been referred to as in vitro
pollination and the development of seed through in vitro
fertilization.
[Ref: MK Rajdan]
4. History
• German Botanist Harberlandt (1902) develops the concept of in
vitro culture.
•
• This in vitro pollination technique was developed at university
of Delhi to produce hybrid among species of pavaceraceae and
solanece.
[Ref: Maheshwari and kanta, 1964]
Barriers during pollination and fertilization of in vitro
technique
• Pollination and fertilization under in vitro condition offer an
opportunity for producing hybrid embryos among plants that
can’t be crossed by conventional method of plant breeding.
• In hybridization programs, transferring viable pollen from one
parent to another does not always lead to seed setting.
5. Some of the barriers to fertilizations are pre-fertilization/pre
zygotic Barriers:
Inability of pollen to germinate on foreign stigma.
Failure of the pollen tube to reach the ovule due to excessive
length of the style or slow growth of the pollen tube, which fails to
reach the base of the style before the ovary abscises.
Bursting of the pollen tube in the style.
These are pre-fertilization or pre-zygotic Barriers-
• Post Zygotic Barriers:
Fertilization may occur normally, but the hybrid embryo fails to attain
maturing due to embryo-endosperm incompatibility, or poor development
of endosperm. It is called post zygotic barriers.
6. Circumvent of Barriers:
• From time to time various techniques have been developed to
circumvent the pre zygotic Barriers to fertility. Some of these are-
o Bud pollination
o Stub pollination
o Heat treatment of the style
o Mixed pollination
o Irradication
• The possibility of effecting fertilization by introducing pollen grains
directly into the ovary (intra-ovarian pollination) is yet another
approach to bypass the pre-fertilization barriers.
• A still more promising and proven technique developed by
Maheshwari and his students to overcome the pre-zygotic barriers to
fertility is what they have described as ‘test tube fertilization’.
• Post fertilization barrier may overcome by the culture of ovaries by
ovule culture after pollination
7. Types of in vitro pollination
• Ovular pollination:
Application of pollen to
excised ovule.
• Ovarion pollination:
Application of pollen to
excised ovary.
• Placental pollination:
Application of pollen to
ovules attached to the
placenta.
• Stigmatic pollination:
Application of pollen to
stigma.
8. Technique:
Materials required:
• Ovaries which are large and contain many ovules are the best
experimental material for in vitro pollination.
• Pollen which should be viable and able to germinate.
• 1% CaCl2 solution that favour the growth of pollen tube.
Disinfection of materials:
• A reasonable disinfection of ovule and pollen is the principle
requirement for in vitro pollination.
• Flower buds are emasculated before anthesis and bagged in order to
prevent pollination. The buds are brought to the laboratory for aseptic
culture. The whole pistil are sterilized by 70% alcohol surface
sterilized with a suitable agent and finally washed with distil water.
• To collect pollen under aseptic condition, anthers removed from the
flower are kept in sterile petriplates containing a filter paper until their
dehiscence. The pollen is then aseptically deposited on the cultured
ovules, placental or stigma depending on the nature of the
experiment.
9. Culture of ovules, ovary and stigma:
Ovules:
The growth of pollen tube attached to bare ovules is inhibited by
the presence of water on the surface of the ovules.
This film of water should be dried with filter paper and later the
dried ovules covered by the pollen grain.
In Nicotiana tabacam, Allium cepa, Gynandropsis gynandra seeds
are raised from ovules which contain globular or older embryo.
6 days after in vitro pollination ovules contain a single celled
zygote which requires more complex growth condition.
10. For the development of subsequent embryonic stages, ovules
which have been self-pollinated are usually kept on the placenta
until seed formation while cross pollinated ovules regaine placenta
only during the initial 6-8 days of culture.
Afterwards, they can be transferred to fresh medium without
placenta.
Use:
Ovule culture has proved to be very useful
technique for raising inter specific hybrids within
genus Gossypium herbacium and Trifalium.
11. Ovary:
The technique of ovary culture was developed by Nitsch in 1951
by the ovaries of Cucumis and Lycopersicon excised from
pollinated flower in vitro to develop into mature fruits.
Medium:
Successful culture excised ovaries from a number of species such as
Linaria macroccana, Hyoscymus niger on a medium containing
mineral salts and sucrose.
The addition of vitamin B to the medium resulted in the development of
fruits of normal size with viable seeds.
Further enrichment by IAA or coconut milk induced even larger fruits.
12. Floret envelops:
The floret envelops play an important role in the development of the
fruit and the embryo of monocots.
Ovary excised soon after pollination only when the floret envelop
remain intact. E.g. Triticum aestivum and Triticum spelta.
Hull factor:
This requirement of the floret envelops associating with excised
monocot ovules in vitro is known as ‘hull factor’.
In the elongation of barely embryo cells can take place but cell division
doesn’t occur.
Use of ovary culture:
Several interspecific and intergeneric hybrids can be produced
between sexually incompatible parents in the family Cruciferae with the
aid of ovary culture.
13. • Stigma:
The entire placenta or part of it bearing the ovules is used in placenta
pollination.
To perform in vitro stigmatic pollination the excised pistils are carefully
surface
sterilized without wetting the stigma with the sterilant solution.
Sometimes the
entire pistil in which
the placental bearing
ovules have been
exposed are cultured
to study the effect of
placental and stigmatic
pollination in the same
pistil.
In stigmatic pollination
presence of perianth
is important factor
in dicot.
14. Factor affecting seed set
Physiological state of the explant:
The physiological state of the pistil at the time of excising the ovules or
ovary influences the seed set after in vitro pollination.
Wetting surface of the ovules or stigma may lead to poor pollen
germination or bursting of the pollen tubes and poor seed set.
Pollen germination on the stigma and growth of the pollen tube
influences the synthesis of proteins which may sometimes inhibit the
entry of the pollen tube into the ovary.
To improve the chances of success of in vitro pollination the level of
incompatibility should be reduced.
The time of excising the ovules from pistil has a definite influences on
seed set after in vitro pollination.
Ovules excised 1-2 days after anthesis show a higher seed set.
15. Culture medium:
• 1: The nutrient medium plays an important role in supporting the normal
development of ovary and ovules in culture until seed formation.
• 2: Nutrient medium on successful culture of ovules include Nitsch’s mineral salts,
white’s vitamins and 5% sucrose.
• 3: Several orchid ovules isolated from pollinated ovaries can grow successful on
simple 10% sucrose solution and Zephyranthes require coconut milk or casamino
acids.
• 4: Source of reduced N2 as a complete amino acid mixture is require for optimal
kernel development and growth.
• 5: Kinetin promotes the initial growth of the embryo. 10mgL-1 IAA or 0.1mg kinetin
improves the no. of seeds per ovule.
• 6: Nitsch’s medium is appropriate for in vitro culture of pollinated ovules of most
species.
• 7: Osmolarity of the culture medium also affects the development of excised
ovule.
• Sucrose anywhere in the range 4-10%.
17. Storage condition:
• Usually the first step of this process occurs at room temperature and
without special lighting.
[Zenk teller-1980]
• The ovary cultures are maintained at 22-26 0C and other suitable
conditions favouring embryogenesis.
Genotype:
• The response of in vitro ovaries in relation to the seed set depends on
the species.
• Pollen grains of crucifers are difficult to germinate in culture. Brassica
oleracea ovules in 1% solution of CaCl2 with 10% gelatin and then
pollinated with pollen transferred to Nitsch’s medium until seed set.
• Pollen grains of crucifers are difficult to germinate in cultures and a
modified technique is required to obtain germinable seed.
18. Application of in vitro pollination:
In plant breeding programs, the technique of in vitro pollination has potential
application in different areas-
• Overcoming self-incompatibility: Petunia axilaris and Petunia hybrida
are self-incompatible species. Germination of pollen is good on self-
pollinated pistils but a barrier exists in the zone of the ovary as a result, the
pollen tube cannot fertilize the ovule. The barrier of these taxa can be
overcome by in vitro pollination.
• Overcoming cross-incompatibility: Successful culture of in vitro
pollinated ovules has raised the possibility of producing hybrids which are
unknown because of pre-fertilization incompatibility barriers.
• Production of haploid plant: Another application of in vitro pollination
reported, is the production of haploids of Mimulus luteus CV. Tigrinus
grandiflorus by pollinating its exposed ovules with Torenia fournieri. The
haploids of Mimulus luteus developed parthenogenetically, which
otherwise could not be obtained through anther culture.
19. Some other examples that produces hybrid parthenogenitically through
in vitro pollination are Nicotiana tabacum, Hordeum vulgare, Triticum
aestivum.
• Production of stress-tolerant plant: Maize plants tolerant to beat
stress have been produced through in vitro pollination at high
temperature. Additionally these plants exhibited increased vigour and
grain yield.
• Development of young hybrid embryo: Development of young
hybrid embryos can be achieved in extremely widely crosses through
in vitro pollination. The efficiency of this technique needs much
improvement.
Purpose of in vitro pollination
Intergeneric hybridization
Intraspecific hybridization
Interspecific hybridization
Intra-familiar crossing
20. Why in vitro pollination is needed?
For the production of homozygous plant.
For the conservation of extinct plant species.
Hybrid production
Reducing the breeding cycle.
Overcome the dormant period.
Production of hybrid species by distant hybridization.
Production of haploid plant.
Conservation of germplasm.
In vitro fertilization using isolated single gamete
A Landmark technique developed recently in the field of plant
biotechnology has been the successful fusion of male and female
gametes isolated from higher plants in vitro and subsequent
regeneration of fusion product into embryo and finally a plant.[Kraz
and Lorz, 1993]. This process is known as in vitro fertilization requires
isolation of male gametes sperms from germinating pollen grainer
tube and of the female gamete (egg) from embryo sac.
21. Fusion of isolated gametes, development of zygote, embryo and
plant take place in the absence of surrounding tissues. Thus in
vitro fertilization using isolated higher plant gametes I different from
that in vivo.
Method:
The methodology of gamete isolation there in vitro fusion, and culture
has been standardized for maize plant. [Kranz, 1999]
Isolation of sperm from pollen grains is executed by osmotic shock in
mannitol solution.
Isolation of ovules is done by micro-dissection of ovule incubated to
40-60 minutes at 24±0.5 0C in enzyme solution set at PH 5.
Microdroplet mannitol solution placed on UV sterilized cover slip with
the aid of micropillaries connected to a computed controlled dispenser
to isolate and select the egg cell.
22. Method
The cover slips the over layed with 300µl autoclaved mineral oil.
By using micropump isolated sperm is transferred into microdroplet
containing egg.
After fixing, egg is fertilizing by electrofusion because of supplying
maximum of B negative DC pulses.
Fertilize then cultured on semipermeable transparent membrane of a
‘Millicell-CM’ dish filled with 0.1 ml of nutrient solution.
In 50 µEm-2s-1 light intensity, 26±10C temperature the dish is then
inserted in the middle of 3 cm perriplate where 1.5 of a feeder cell
suspension layer of another maize line remains.
A high frequency of sperm-egg fusion was reported.
Fertilized egg divided to from embryos from which regenerated full
plants within 86 days.
23. Reference
Bhojwani S.S and Rajdan M.K, 1983 – Plant tissue
culture : Theory and practice
Elsevierscience publisher, Amsterdom, Oxford, New York Tokyo.
www.wikipidia.com
That’s all from our presentation