Hybridization between individuals from different species belonging to the same genus or two different genera, is termed as distant hybridization or wide hybridization, and such crosses are known as distant crosses or wide crosses.
Hybridization between individuals from different species belonging to the same genus or two different genera, is termed as distant hybridization or wide hybridization, and such crosses are known as distant crosses or wide crosses.
The term balanced tertiary trisomic has three words of which (1) “trisomic” indicates the presence of extra chromosome, (2) “tertiary” indicates that the extra chromosome is a trans-located chromosome, and (3) “balanced” refers to the breeding behaviour of the trisomic.
Ramage defined the BTT as a tertiary trisomic constructed in such a way that the dominant allele of a marker gene, closely linked with the translocation breakpoint of the extra chromosome is carried on the extra chromosome, and the recessive allele is carried on the two normal chromosomes that constitute the diploid complement. The dominant marker gene may be located on the centromere segment or the trans-located segment of the extra chromosome.
The term balanced tertiary trisomic has three words of which (1) “trisomic” indicates the presence of extra chromosome, (2) “tertiary” indicates that the extra chromosome is a trans-located chromosome, and (3) “balanced” refers to the breeding behaviour of the trisomic.
Ramage defined the BTT as a tertiary trisomic constructed in such a way that the dominant allele of a marker gene, closely linked with the translocation breakpoint of the extra chromosome is carried on the extra chromosome, and the recessive allele is carried on the two normal chromosomes that constitute the diploid complement. The dominant marker gene may be located on the centromere segment or the trans-located segment of the extra chromosome.
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
Fluorescent in situ hybridization (FISH) is a cytogenetic technique that can be used to detect and localize the presence or absence of specific DNA sequences on chromosomes.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
2. Submitted to:-
Dr. P. C. Patel
Assistant Professor, Dept. of GPB
SDAU, S.K. Nagar
Submitted by:-
Vaghela Gauravrajsinh K
M.Sc. (Agri.)
Reg.no:-04-AGRMA-01840-2018
SDAU, S.K. Nagar
Wide Hybridization and Their application in
crop improvement
3. CONTENT
1) Introduction
2) History of Distant Hybridization
3) Objective of Distant Hybridization
4) Features
5) Barriers associated with Distant Hybridization
6) Techniques for production of Distant Hybrid
7) Role of Wide crossing in crop improvement
8) Limitations of Distant Hybridization
9) Achievements
4. HYBRIDIZATION
Hybridization:- Mating between two different strains.
Interspecific Hybridization:- When the individuals from two distinct species of the genus
are crosssed, it is known as interspecific hybridization. e.g. Oryza sativa x Oryza perennis.
Intergeneric Hybridization:- When the individuals being crossed belong to species from
two different genera it is referred as intergeneric hybridization. e.g. Triticum spp. X rye
(Secale cereale).
Distant Hybridization:- Hybridization between individuals from different species,
belonging to the same genus or to different genera is termed as distant hyridization and such
crosses are known as distant crosses or wide crosses.
5. HISTORY
Thomas Fairchild (1717):- He first authentic record of a
distant hybridization for crop improvement is the production
of a hybrid between Carnation (Dianthus caryophyllus) and
Sweet William (Dianthus barbatus).
Karpechenko (1928):- An interesting intergeneric hybrid,
Raphanobrassica, (R. sativus x B. oleracea) was produced.
Rimpu (1890):- Produce the first intergeneric hybrid
triticale which have greaterpotential than Raphanobrassica.
Thomas Fairchild
Karpechenko
6. OBJECTIVES DISTANT HYBRIDIZATION
Wide crossing or distant hybridization has been used in the genetic
improvement of some crop plants. It is an effective means of transferring
desirable genes into cultivated plants from related species and genera.
7. INTER- SPECIFIC HYBRIDIZATION
Ex. Nerica, an upland rice forAfrica
Oryza sativa (Asian upland rice) : non-shattering , resistant to lodging,
high yield potential
Oryza glaberrima (African rice) : drought tolerant, disease resistant, weed
suppressing
Nerica rice combines the best of both species.
10. INTERGENERIC CROSSES
Triticale, a new cereal created in the lab.
Triticale, a cross(intergeneric cross) between wheat and rye , was produced by
embryo rescue of the product of fertilization and a chemically induced doubling
of the chromosomes.
Embryo rescue become necessary when fertile offspring is never produced by an
interspecific cross.
13. Main features of Interspecific or
Intergeneric hybridization
1.It is used when the desirable character is not found within the species ofa crop.
2.It is an effective method of transferring desirable gene into cultivated plants from
their related cultivated or wild species.
3.It is more successful in vegetatively propagated species like sugarcane and
potato than in seed propagated species.
4.It gives rise to three types of crosses viz. a) fully fertile, b) Partially fertile and
c) Fully sterile in different crop species.
5.It leads to introgression which refer to transfer of some genes from one
species into genome of another species.
6.F1 hybrid between two genus are always sterile. The fertility has to be restored by
doubling of chromosome through colchicinetreatment.
14. Interspecific hybridization gives rise to
three types of crosses
a) Fully fertile
b) Partially fertile
c) Fully sterile in different crop species
15. Fully fertile crosses
Interspecific crosses are fully fertile between those species that have complete
chromosomal homology. Chromosome in such hybrids have normal pairing at
meiosis and result the F1 plants are fully fertile.
• Example- Cotton, Wheat, oat and Soybean.
Cotton: There are four cultivated species of cotton Viz.,
• G. hirsutum and G. barbadense (Tetraploid,2n=52).
• G. arboreum and G. herbaceum (Diploid,2n=26).
Triticum aestivum* Triticum compactum ( Where * F1 plants are Fully fertile)
16. Partially fertile crosses
Interspecific crosses are partially fertile between those species which differ in
chromosome number but have some chromosome in common.
• In such situation , F1 plants are partially fertile and partially sterile.
• Example- Wheat, Cotton, Tobacco.
Cotton: G. hirsutum (AADD) X G. thurberi (DD)
2n=52 2n=26|
F1(ADD)
13II + 13I
Partially sterile or fertile, 2n=26.
17. Fully sterile crosses
Interspecific crosses are fully sterile between those species which do not
have chromosomal homology. Such hybrids can be made self fertile by
doubling the chromosomes through colchicine treatment e.g. Tobacco,
wheat, cotton, brassica and Vigna species.
Cotton : G. arboreum (2n=26 ) X G. thurberi(2n=26)
|
F1was sterile
Colchicine treatment- Fertile amphidiploid 2n=52.
19. CROSS INCOMPATIBILITY
This is the inability of the functional pollen grains of one species or genus to effect
fertilization in another species or genes.
There are three main reasons of cross incompatibility viz.
i. Lack of pollen germination,
ii. Insufficient growth of pollen tube to reach ovule and
iii. Inability of male gamete to unite with the egg cell.
• These barriers are known as pre –fertilization barriers.
• This is overcome by employing different techniques like reciprocal crosses, bridge
crosses, using pollen mixtures, pistil manipulations, use of growth regulators etc.
20. HYBRID INVIABILITY
This refers to the Inviability of the hybrid zygote or embryo. In some cases, zygote
formation occurs, but further development of the zygote is arrested. In some other cases,
after the completion of the initial stages of development, the embryo gets aborted.
• The reasons for this are:
1. Unfavorable interactions between the chromosomes of the two species
2. Unfavorable interaction of the endosperm with the embryo.
3. Disharmony between cytoplasm and nuclear genes
• Reciprocal crosses, application of growth hormones and embryo rescue are the
techniques that can be used to overcome this problem.
21. HYBRID STERILITY
This refers to the inability of a hybrid to produce viable offspring. This is more
prominent in the case of intergeneric crosses. The major reason for hybrid sterility is the
lack of structural homology between the chromosomes of the two species.
This may lead to meiotic abnormalities like chromosome scattering, chromosome
extension, lagging of chromosome in the anaphase, formation of anaphase bridge,
development of chromosome rings and chains, and irregular and unequal anaphase
separations.
These irregularities may lead to aberrations in chromosome structure. Lack of
homology between chromosomes may also lead to incomplete pairing of
chromosomes.
Sterility caused by structural differences between the chromosomes of two species can
be overcome by amphidiploidization using colchicine.
22. HYBRID BREAKDOWN
Hybrid breakdown is a major problem in interspecific crosses.
When F1 hybrid plants of an interspecific crosses are vigorous and fertile but
there F2 progeny is weak and sterile it is known as hybrid breakdown.
So hybrid breakdown hinders the progress of interspecific gene transfer.
This may be due to the structural difference of chromosomes or problems
in gene combinations.
23. EMBRYO RESCUE
Embryo rescue :
When embryos fails to develop due to endosperm degeneration, embryo
culture is used to recover hybrid plants; this is called hybrid rescue.
e.g :- H. vulgare x Secale cereale.
Embryo rescue generally used to overcome endosperm degeneration.
24. Embryo culture.
A. Proembryo dissected 3 to 5 days after pollination
B. Proembryo culture on solid agar media
C. Plantlet developing from embryo
D. Plantlet transplanted into soil.
25. Embryo rescue in barley
Hordeum vulgare (Barley)
2n =14
Hordeum bulbosum (Wild relative)
2n =2X= 14
X
Embryo Rescue
Haploid Barley 2n =X=7 (H. bulbosum)
chromosomes eliminated
This technique was once more efficient than microspore culture in creating
haploid barley
26. Wide crossing of wheat and rye requires embryo
rescue and chemical treatments to double the no. of
chromosomes triticale
Triticum durum (4X)
AABB
Secale cereale (2X)
RR
x
ABR F1(3x): Embryo Rescue
Chromosome Doubling Hexaploid
Triticale
(6x) AABBRR
27. Limitations of embryo rescue
High cost of obtaining new plantlets .
Sometimes deleterious mutations may be induced during the in vitro
phase.
A sophisticated tissue culture laboratory and a dependable greenhouse
are essential for success.
Specialized skill for carrying out the various operations are required.
28. Differences between Interspecific and
Intergeneric Hybridization
Particular Interspecific Hybridization Intergeneric Hybridization
Parents involved Involves two different species of the same
gene.
Involves two different genera of
the same family.
Fertility Such hybrids vary from completely fertile
to completely sterile
Hybrids are always sterile.
Seed Setting More than intergeneric crosses. Less than interspecific crosses.
Use in crop improvement More than intergeneric crosses. Less than interspecific crosses.
Release of Hybrid Variety Possible in some crops. Not Possible.
Evolution of new crops Not possible, but evolution of new species
is sometimes possible.
Sometime possible,
e.g., Triticale.
29. Techniques to make wide crosses successful
SELECTION OF PLANTS
The most compatible parents available should be selected for the crosses.
RECIPROCAL CROSSES
Reciprocal cross may be attempted when one parental combination fails.
e.g. Mung x udid- cross compatible and Udid x mung-cross incompatible
MANIPULATION OF PLOIDY
Diploidization of solitary genomes to make them paired will be helpful to make the cross fertile.
BRIDGE CROSSES
When two parents are incompatible, a third parent that is compatible with both the parents can be
used for bridge crosses and thus it becomes possible to perform cross between the original parents.
e.g. Tobacco
Nicotiana repanda x N.tabaccum– cross incompatible
Nicotiana repanda x N.sylvestris- cross compatible
Nicotiana syivestris x N.tabaccum- cross compatible Continue.......
30. USE OF POLLEN MIXTURE
Unfavorable interaction between pollen and pistil in the case of wide crosses can be
overcome to some extent by using pollen mixture.
MANIPULATION OF PISTIL
Decapitation of the style will sometimes prove helpful in overcoming incompatibility.
USE OF GROWTH REGULATORS
Pollen tube growth can be accelerated by using growth hormones like IAA, NAA, 2,4-D
and Gibberellic acid.
PROTOPLAST FUSION
When fusion of gametes fails, protoplast fusion of somatic cells can be attempted.
EMBRYO RESCUE
Hybrid zygotes formed by wide crosses may fail to grow in a number of cases. The zygotes
are taken out and grown in in vitro medium to overcome this problem.
31. Role Of Wide Crosses In Crop Improvement
Wide crosses are generally used to improve crop varieties for disease resistance, pest resistance, stress
resistance, quality, adaptation, yield etc. These crosses can even be used to develop new crop species.
Techniques like alien addition and alien substitution may also be effective.
(A)Disease and insect resistance
Crop Character transferred Species transferred from Species transferred to
Cotton Jassid resistance
Blackarm resistance
G. tomentosum
G. arboreum
G. hirsutum
G. barbadense
Okra Resistance to YMV Abelmoschus manihot A. esculenta
Groundnut Resistant to leaf chewing
insect
Arachis monticola A. hypogea
Wheat Rust resistance Agropyron T. aestivum
Tobacco Resistant to mosaic virus N. repanda N. Tabaccum
Sugarcane Sereh disease resistant Saccharum spontaneum S. Officinarum
Potato Resistant to late blight and
leaf roll.
Solanum denissum S. tuberosum
Continue.......
32. (B) Improvement in quality
Crop Charactertransferred Speciestransferred from Speciestransferred to
Cotton Fibre length
Male sterility
G. thurberi&
G. raimondii
G. harkenssii
G.hirsutum
G.hirsutum
Potato Starchcontent Frostresistance Wild species
Solanumacaule
CultivatedSpp.
S.tuberosum
Tomato Carotenoid content Lycopersicon
Wild Spp.
L.esculentum
Palm Oil quality Wild Spp. Cultivated Spp.
Rice,Oat &Rye Protein quality Wild Spp. Cultivated Spp.
Tobacco Leaf quality Nicotiana debneyi N. tabacum
Oat High oil content Avena sterilis A.sativa
(C) Improvement in yield: This also been achieved through the use of wild Spp. in some crops e.g. Oat,
Mung bean, Groundnut, Potato,Tobacco.
33. ALIEN ADDITION LINES
These lines carries one chromosome pair from a different species in addition to the
normal somatic chromosome complement of the parent species.
When only one chromosome (not a pair of chromosome) from another species is
present, it is known as alien addition monosome.
Alien addition have also been done in rice, sugar beet, cotton, brassicas.
The main purpose of alien addition is the transfer of disease resistance from related wild
species. e.g. Transfer of mosaic resistance from Nicotiana glutinosa to N. tabacum.
The alien addition lines have been developed in case of wheat, oats, tobacco and
several other species.
Alien addition lines are of little agricultural importance since the alien chromosome
generally carries many undesirable genes. e.g. Reduced growth and short, broad leaves
in addition to mosaic resistance.
34. ALIEN SUBSTITUTION LINES
This line has one chromosome pair from a different species in place of the chromosome pair
of the recipient species.
When a single chromosome (not a pair) from different species in place of a single
chromosome of the recipient species, known as alien-substitution monosome.
Alien –substitution line have been developed in wheat, cotton, tobacco, oats, etc.
In case of tobacco, mosaic resistance gene N was transferred from the N. glutinosa to N.
tabacum line had 23 pairs of N. tabacum chromosomes and one pair (chromosome H) of N.
glutinosa chromosomes.
The alien substitution show more undesirable effects than alien additions and as a
consequence are of no direct use in agriculture.
35. Limitations of Distant hybridization
1) Incompatible crosses
2) F1 sterility
3) Problems in creating new species
4) Lack of homoeology between chromosome of the parental species
5) Undesirable linkages
6) Problems in the transfer of recessive oligo genes and quantitative traits
7) Lack of flowering in F1
8) Problems in using improved varieties in distant hybridization
9) Dormancy
36. Achievements
Hybrid varieties:-
Upland cotton – MCU-2, MCU-5, Khandwa1, Khandwa2 etc are derivatives of
interspecific hybridization.
Hybrid between Pearl millet x Napier grass - Hybrid Napier which is very popular for
its high fodder yield and fodder quality e.g. Jaywant and Yashwant
Interspecific hybrids in cotton- Varlaxmi, Savitri, DCH-32, NHB-12, DH- 7, DH-9
etc.
Prabhani Kranti variety of bhindi.
