This document discusses different types of male sterility in plants, including genetic male sterility (GMS), cytoplasmic male sterility (CMS), and chemically-induced male sterility (CHA). It describes how each type of male sterility works and how it can be used for hybrid seed production. Specifically, CMS uses cytoplasmic genes to induce sterility and requires maintainer and restorer lines, while GMS uses nuclear genes and can be environmentally sensitive. The document also covers transgenic systems like Barnase/Barstar and provides examples of major crops where male sterility systems have been applied.
Plant breeding methods of vegetatively propagated crops Roksana Aftab Ruhi
Vegetatively propagated crops are bred by intentionally crossing of closely or distantly related individual to produce new crop varieties or lines with desirable traits. Breeding of vegetative crops have successfully improved quality, yield, tolerance of crops to environmental pressure. Breeding helps in producing crops that are resistant to viruses, fungi and bacteria and helps in longer storage period for the harvested crop.
Self-incompatibility refers to the inability of a plant with functional pollen to set seeds when self pollinated. It is the failure of pollen from a flower to fertilize the same flower or other flowers of the same plant.
This presentation includes, Single-locus self-incompatibility- {Gametophytic self-incompatibility (GSI) and Sporophytic self-incompatibility (SSI)},2-locus gametophytic self-incompatibility, Heteromorphic self-incompatibility,Cryptic self-incompatibility (CSI) and Late-acting self-incompatibility (LSI).
Plant breeding methods of vegetatively propagated crops Roksana Aftab Ruhi
Vegetatively propagated crops are bred by intentionally crossing of closely or distantly related individual to produce new crop varieties or lines with desirable traits. Breeding of vegetative crops have successfully improved quality, yield, tolerance of crops to environmental pressure. Breeding helps in producing crops that are resistant to viruses, fungi and bacteria and helps in longer storage period for the harvested crop.
Self-incompatibility refers to the inability of a plant with functional pollen to set seeds when self pollinated. It is the failure of pollen from a flower to fertilize the same flower or other flowers of the same plant.
This presentation includes, Single-locus self-incompatibility- {Gametophytic self-incompatibility (GSI) and Sporophytic self-incompatibility (SSI)},2-locus gametophytic self-incompatibility, Heteromorphic self-incompatibility,Cryptic self-incompatibility (CSI) and Late-acting self-incompatibility (LSI).
Dr.S.KARTHIKUMAR
Associate Professor
Department of Biotechnology
Kamaraj College of Engineering and Technology, K.Vellakulam-625701, TN, India
Email: skarthikumar@gmail.com
this presentation intends to familiarize students with the basic concept of male sterility. this is deemed essential to proceed with the cytoplasmic male sterility.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
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.
Richard's aventures in two entangled wonderlandsRichard 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.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
The increased availability of biomedical data, particularly in the public domain, offers the opportunity to better understand human health and to develop effective therapeutics for a wide range of unmet medical needs. However, data scientists remain stymied by the fact that data remain hard to find and to productively reuse because data and their metadata i) are wholly inaccessible, ii) are in non-standard or incompatible representations, iii) do not conform to community standards, and iv) have unclear or highly restricted terms and conditions that preclude legitimate reuse. These limitations require a rethink on data can be made machine and AI-ready - the key motivation behind the FAIR Guiding Principles. Concurrently, while recent efforts have explored the use of deep learning to fuse disparate data into predictive models for a wide range of biomedical applications, these models often fail even when the correct answer is already known, and fail to explain individual predictions in terms that data scientists can appreciate. These limitations suggest that new methods to produce practical artificial intelligence are still needed.
In this talk, I will discuss our work in (1) building an integrative knowledge infrastructure to prepare FAIR and "AI-ready" data and services along with (2) neurosymbolic AI methods to improve the quality of predictions and to generate plausible explanations. Attention is given to standards, platforms, and methods to wrangle knowledge into simple, but effective semantic and latent representations, and to make these available into standards-compliant and discoverable interfaces that can be used in model building, validation, and explanation. Our work, and those of others in the field, creates a baseline for building trustworthy and easy to deploy AI models in biomedicine.
Bio
Dr. Michel Dumontier is the Distinguished Professor of Data Science at Maastricht University, founder and executive director of the Institute of Data Science, and co-founder of the FAIR (Findable, Accessible, Interoperable and Reusable) data principles. His research explores socio-technological approaches for responsible discovery science, which includes collaborative multi-modal knowledge graphs, privacy-preserving distributed data mining, and AI methods for drug discovery and personalized medicine. His work is supported through the Dutch National Research Agenda, the Netherlands Organisation for Scientific Research, Horizon Europe, the European Open Science Cloud, the US National Institutes of Health, and a Marie-Curie Innovative Training Network. He is the editor-in-chief for the journal Data Science and is internationally recognized for his contributions in bioinformatics, biomedical informatics, and semantic technologies including ontologies and linked data.
1. Assignment
Subject : Advanced Plant Breeding System (GPB903)
Presented by: Mr. Indranil Bhattacharjee
Student I.D. No.: 17PHGPB102
Presented to : Prof. (Dr.) S. Marker
Sam Higginbottom University of Agriculture, Technology &
Sciences
Allahabad-211007
Male Sterility
2. Male Sterility
•Male sterility is characterized by nonfunctional pollen
grains, while female gametes function normally.
•Inability to produce or to release viable or functional pollen
as a result of failure of formation or development of
functional stamens, microspores or gametes.
•Main reason is mutation.
3. Manifestations of Male Sterility
•Absence or malformation of male organs.
•Failure to develop normal microsporogenous tissue-
anther
•Abnormal microsporogenesis (deformed or inviable
pollen)
•Abnormal pollen maturation
•Non dehiscent anthers but viable pollen, sporophytic
control
•Barriers other than incompatibility preventing pollen
from reaching ovule
4. History of Male Sterility
•J.K. Koelreuter (1763) observed anther abortion within species
& species hybrids.
•Genic male sterility has been reported in cabbage (Rundfeldt
1960), cauliflower (Nieuwhof 1961)
•Male sterility systems have been also developed through
genetic engineering (Williams et al. 1997) and protoplast fusion
(Pelletier et al. 1995)
•Male sterility were artificially induced through mutagenesis
(Kaul 1988)
5. There are several forms of pollination control
•Manual emasculation
•Use of male sterility
•Use of self-incompatibility alleles
•Use of male gametocides
•Use of genetically engineered “pollen killer” genetic system
Why Male Sterility ???
•Reduced the cost of hybrid seed production.
•Production of large scale of F1 seeds.
•Avoids enormous manual work of emasculation and pollination.
•Speed up the hybridization programme.
•Commercial exploitation of hybrid vigour.
6. Modes of Creating Male Sterility
•Spontaneous mutations
•Interspecific hybridization
•Mutation induction (Ethidium Bromide)
•Genetic Engineering
•Chemically induced male sterility (CHAs)
7. Detection of Male Sterility system
Whether a particular sterile genotype belongs to which MS
system can be detected by its progeny performance on crossing
with a few normal genotypes.
•Trend-I- All progenies in all the rows may be sterile- CMS
•Trend-II- Some rows may consist all fertile Some rows sterile
and fertile in 1:1 ratio- GMS
•Trend-III- Some rows fertile. Some rows sterile and some rows
sterile and fertile in 1:1 ratio - CGMS
8. Classification of Male Sterility
Kaul (1988) Classified Male Sterility in three major groups
1. Phenotypic Male Sterility (Morphological)
I. Structural or Staminal Male Sterility
II. Pollen Male Sterility
III. Functional Male Sterility
2. Genotypic Male Sterility
I. Genetic Male Sterility (GMS)
II. Environmental Sensitive (EGMS)
a) Thermo sensitive genetic male sterility (TGMS)
b) Photoperiod sensitive genetic male sterility (PGMS)
III. Environmental non-sensitive
IV. Cytoplasmic Male Sterility (CMS)
V. Cytoplasmic Genetic Male Sterility (CGMS)
VI. Transgenic Male Sterility (TMS)
3. Chemically Induced Male Sterility (CHA)
9. Phenotypic Male Sterility
1. 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).
2. Structural or staminal male sterility: in which male flowers
or stamen are malformed and non functional or completely
absent.
3. Functional male sterility: in which perfectly good and
viable pollen is trapped in indehiscent anther and thus
prevented from functioning
10. Cytoplasmic Male Sterility (CMS)
•Determined by the cytoplasm (mitochondrial or chloroplast genes).
•Result of mutation in mitochondrial genome (mtDNA)- Mitochondrial
dysfunction.
•Progenies would always be male sterile since the cytoplasm comes
primarily from female gamete only.
•Nuclear genotype of male sterile line is almost identical to that of the
recurrent pollinator strain.
•Male fertile line (maintainer line or B line) is used to maintain the
male sterile line (A line).
•CMS is not influenced by environmental factors (temperature) so is
stable.
11. Utilization of CMS in Plant Breeding
•CMS can used in hybrid seed production of certain ornamental
species or in species where a vegetative part is of economic
value.
•But not for crop plants where seed is the economic part
because the hybrid progeny would be male sterile.
•This type of male sterility found in onion, fodder jowar,
cabbage etc.
14. Genetic Male Sterility (GMS)
Also called as nuclear male sterility.
•Mostly governed by single recessive gene (ms) but dominant gene
governing male sterility (safflower).
•Origin: Spontaneous mutation or artificial mutations (Gamma rays,
EMS) are common.
•‘ms’ alleles may affect staminal initiation, stamen or anther sac
development, PMC formation, meiosis, pollen formation,
maturation and dehiscence.
15. Types of GMS
•Environment insensitive GMS: ms gene expression is much less
affected by the environment.
•Environment sensitive GMS: ms gene expression occurs within
a specified range of temperature and /or photoperiod regimes
(Rice, Tomato, Wheat etc.).
1. TGMS: sterility is at particular temperature e.g. In rice TGMS
line (Pei- Ai645) at 23.30C (China).
a.TGMS at high temperature is due to failure of pairing of two
chromosomes at metaphase was evident.
b.This abnormality led to abnormal meiosis, abnormal or
sterile pollens.
c.Anthers were shriveled and non-dehiscence-Male sterile.
d.However, these lines produced normal fertile pollen at low
temp.
Sensitive period : PMC formation to Meiosis
16. 2. PGMS: Governed by 2 recessive genes.
Sterility is obtained in long day conditions while in short days,
normal fertile plant.
Rice:- Sterile under Long day conditions (13 hr. 45 min + Temp.
23-290 C) but fertile under short day conditions.
Sensitive period: Differentiation of secondary rachis branches to
PMC formation
19. Cytoplasmic Genetic Male Sterility (CGMS)
•CGMS is also known as nucleoplasmic male sterility.
•Case of CMS, where a nuclear gene (R) for restoring fertility in
male sterile line is known.
•R (restorer gene) is generally dominant can be transferred from
related strains or species.
•This system is known in cotton, maize, jowar, bajra, sunflower,
cotton, rice and wheat etc.
26. Limitations of Cytoplasmic-Genetic Male Sterility
•Undesirable effects of the cytoplasm
•Unsatisfactory fertility restoration
•Unsatisfactory pollination
•Spontaneous reversion
•Modifying genes
•Contribution of cytoplasm by male gamete
•Environmental effects
•Non availability of a suitable restorer line
27. Transgenic Male Sterility
•Recombinant DNA techniques for disturbing any or number of
developmental steps required for the production of functional
pollen within the microspore or for the development of any somatic
tissues supporting the microspores.
•Transgenes for male sterility are dominant to fertility.
•Also to develop effective fertility restoration system for hybrid seed
production.
•Example: Barnase/Barstar system
28.
29. •Barnase is extracellular RNase; barstar is inhibitor of barnase
(Bacillus amyloliquefaciens)
•Plants with TA29 promoter-Barnase construct are male sterile
•Those with TA29-Barstar are not affected by the transgene
barnase.
•Barstar is dominant over the Barnase
•Fuse the barnase and barstar genes to TA29 promoter–TA29 is a
plant gene that has tapetum specific expression.
•Cross male sterile (barnase) with male fertile (barstar) to get
hybrid seed, which now has both barnase and barstar expressed
in tapetum and, hence, is fully fertile
32. Chemical Induced Male Sterility
•CHA is a chemical that induces artificial, non-genetic male sterility
in plants so that they can be effectively used as female parent in
hybrid seed production.
•Also called as Male gametocides, male sterilants, selective male
sterilants, pollen suppressants, pollenocide, androcide etc.
•The first report was given by Moore and Naylor (1950), they
induced male sterility in Maize using maleic hydrazide (MH).
33. Properties of an Ideal CHA
•Must be highly male or female selective.
•Should be easily applicable and economic in use.
•Time of application should be flexible.
•Must not be mutagenic.
•Must not be carried over in F1 seeds.
•Must consistently produce >95% male sterility.
•Must cause minimum reduction in seed set.
•Should not affect out crossing.
•Should not be hazardous to the environment
35. Hybrid Seed Production based on CHAs
Conditions required:-
1. Proper environmental conditions (Rain, Sunshine, temp, RH
etc.)
2. Synchronisation of flowering of Male & Female parents.
3. Effective chemical emasculation and cross pollination
4. CHA at precise stage and with recommended dose
5. GA3 spray to promote stigma exertion.
6. Supplementary pollination to maximise seed set
7. Avoid CHA spray on pollinator row.
36. Advantages of CHAs
•Any line can be used as female parent.
•Choice of parents is flexible.
•Rapid method of developing male sterile line.
•No need of maintaining A,B&R lines.
•Hybrid seed production is based on only 2 line system.
•Maintenance of parental line is possible by self pollination.
•CHA based F2 hybrids are fully fertile as compared to few
sterile hybrids in case of CMS or GMS.
37. Limitations of CHAs
•Expression and duration of CHA is stage specific.
•Sensitive to environmental conditions.
•Incomplete male sterility produce selfed seeds.
•Many CHAs are toxic to plants and animals.
•Possess carryover residual effects in F1 seeds.
•Interfere with cell division.
•Affect human health.
•Genotype, dose application stage specific.
38. Significance of male Sterility in Plant Breeding
•Male sterility a primary tool to avoid emasculation in
hybridization.
•Hybrid production requires a female plant in which no viable
pollens are borne. Inefficient emasculation may produce some self
fertile progenies.
•GMS is being exploited (Eg.USA-Castor, India-Arhar).
•CMS/ CGMS are routinely used in Hybrid seed production in corn,
sorghum, sunflower and sugarbeet, ornamental plants.
•Saves lot of time, money and labour.
39. Limitations in using Male Sterile line
•Existence and maintenance of A, B & R Lines is laborious and
difficult.
•If exotic lines are not suitable to our conditions, the
native/adaptive lines have to be converted into MS lines.
•Adequate cross pollination should be there between A and R
lines for good seed set.
•Synchronization of flowering should be there between A & R
lines.
•Fertility restoration should be complete otherwise the F1 seed
will be sterile Isolation is needed for maintenance of parental
lines and for producing hybrid seed.
41. Male sterility system in Rice hybrid seed
production
Male sterility: a condition in which the pollen grain is unviable or cannot germinate
and fertilize normally to set seeds.
Male Sterility Systems (genetic and non-genetic):
• Cytoplasmic genetic male sterility (CMS)
Male sterility is controlled by the interaction of a genetic factor (S) present in
the cytoplasm and nuclear gene (s).
• Environment-sensitive genic male sterility (EGMS)
Male sterility system is controlled by nuclear gene expression, which is
influenced by environmental factors such as temperature (TGMS), daylength
(PGMS), or both (TPGMS).
• Chemically induced male sterility
Male sterility is induced by some chemicals (gametocides)
46. Advantage & Disadvantage of 2-line hybrid rice
system
Advantages
•Simplified procedure of hybrid seed production
•Multiple and diverse germplasm available as parents
1) Any line could be bred as female
2) 97% (2-line) vs 5% (3-line) of germplasm as male
•Increased chance of developing desirable & heterotic hybrids
•Multiple cytoplasm courses as female parents
Disadvantages
•Environmental effect on sterility could cause seed purity problem
47. Requirements for 3 Lines in CMS System
A-line
1) Stable Sterility
2) Well developed floral traits for outcrossing
3) Easily, wide-spectum, & strongly to be restored
B-line
1) Well developed floral traits with large pollen load
2) Good combining ability
R-line
1) Strong restore ability
2) Good combining ability
3) Taller than A-line
4) Large pollen load, normal flowering traits and timing
48.
49. Advantage & Disadvantage of 3-line hybrid rice
system
Advantages
•Stable male sterility.
Disadvantages
•Limit germplasm source (CMS, Restorer)
•Dominant CMS cytoplasm in large area (WA)
•One more step for parental seed production
•Time consuming of CMS breeding
50.
51.
52.
53.
54.
55.
56.
57.
58. Male sterility system in Maize hybrid seed
production
Different ways of inducing male sterility in maize
I. Manual/mechanical emasculation (detasselling)
II. Genic male sterility
III. Cytoplasmic genetic male sterility
IV. Gametocides
1. Genetic Male sterility
Male sterility determined by single recessive gene 40 loci involved
have been identified (ms1 to ms52) ms5 –cloned
Problem : impossible to maintain male sterile inbred detasselling
required
59. 2. Cytoplasmic Male sterility
A. CMS-T (Texas) (Rogers and Edwardson, 1952)
•Highly stable under all environmental conditions
•Characterized by failure of anther exertion and pollen abortion
•Susceptible to race T of the southern corn leaf blight -
(Cochliobolus heterostrophus = Bipolaris maydis)
•Widespread use of T-cytoplasm for hybrid corn production led to
epidemic in 1970 with the widespread rise of Race T.
•Toxin produced by C. heterostrophus = T-toxin.
•Fertility restoration is sporophytic
•Rf1 (chr. 3) & Rf2 (chr.9) are responsible for fertility restoration
60. T-urf13 gene in T cytoplasm maize
Mitochondrial gene T-urf13 is a unique chimeric sequence
Effect of URF13 protein-
•Degeneration of the tapetum during microsporogenesis
•Disruption of pollen development leading to male cell abortion
B. CMS-C (Charrua) (Beckett, 1971)
•Mutations in three genes viz atp6, atp 9 and cosII- confer CMS
phenotype
•Fertility restoration is Sporophytic
•Rf4, Rf5, Rf6 are responsible for fertility restoration
C. CMS-S (USDA) (Jones,1957)
•Sterility associated with orf355-orf77 chimeric mt gene
•Fertility restoration is Gametophytic
•Rf3 (chr. 2) are responsible for fertility restoration
•Plasmid like element S1 & S2
61. Reversion to fertility
The reversion of CMS strain to male fertility is based on genetic
change
•Reversion can be spontaneous or mutagen induced
•S-cytoplasm revert rather frequently to male fertility (than T & C).
Maize-CMS Restoration of fertility system: different classes of pollen grains are
produced, but not all of them are viable
62.
63.
64.
65.
66.
67.
68.
69. Male sterility system in Bajra hybrid seed
production
Types of Hybrids
1) Single cross hybrid (A×B)
2) Double cross hybrid (A×B)×(C×D)
3) Three way cross Hybrid (A×B)×C
4) Top cross (C×OPV)
5) Hybrid blends
6) Inter-population hybrids
7) Chance hybrids
70. Hybrid seed production using CGMS
Depends on the cytoplasm that produce male sterility and gene
that restores the fertility.
Steps:
1. Multiplication of CMS (A) line
2. Multiplication of Maintainer (B) line and Restorer (R) line
3. Production of Hybrid seed (A×R)
Maintenace of A & B lines:
i. Grow A line and its corresponding B line together in an
isolated plots.
ii. Isolation distance for A×B production fields is at least 1000m.
iii. A ratio of 1A:1B row is maintained.
iv. Pollens produced by the B line fertilize the male sterile plant
(A) and seeds produced thus
v. Give rise to A line again.
71. Maintenance of R line:
•Pearl millet R line could be either an inbred line or an Open
pollinated variety which can be multiplied as variety.
•Seeds of R lines are produced by multiplying seeds in isolated
plots having distance 1000m.
•Any plant in the R line plot appearing different from true R type
should be uprooted or rogued out before anthesis.
•Purity of the parental seed is very important because it affects the
quality of the hybrid seeds that is generated.
72. Scheme of hybrid seed
production in pearl millet
Layout of hybrid seed
production plot
73. Identification of potential hybrid parents
(A,B and R lines)
•Potential male and female parents for hybrid seed production are
identified by crossing male fertile parent (Inbreds, variety,
germplasm, breeding stocks in advanced generations) to a male
sterile line (A line) and observing their corresponding hybrids in
small plots of an observation nursery.
•A few plants of each cross are subjected to the bagging test i.e.
covering the few panicles with the paper bags before anthesis and
observing the seed set under the bag after few weeks.
74.
75.
76. Crop Source of cytoplasm Drawbacks
Sorghum Combined kafir Black glumes and chalky endosperm
77. Male sterility system in Brassica hybrid seed
production
Cytoplasmic male-sterile
Stamen (anther and filament) and pollen grains are affected
It is divided into:
a. Autoplasmic
•Arisen within a species as a result of spontaneous mutational
changes in the cytoplasm, most likely in the mitochondrial genome
b. Alloplasmic
•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
78. Various CMS systems
1. Raphanus or ogu system
2. Polima or pol system
3. Shiga-Thompson or nap system
4. Diplotaxis muralis or mur system
5. Tournefortii (tour) system
6. Moricandia arvensis or mori system
7. Chinese juncea or jun system
17 systems are available, only difference is the use of male sterile
cytoplasmic sources differs for each system
1. Nap system– B.napuus cross b/w winter & spring var.
2. pol system – B.napus var polima
3. mur system--Diplotaxis muralis x B.campestris cv Yukina
4. tour system– B.juncea collections
79. Ogu system:-
First discovered in Japanese radish (Raphanus sativus) by Ogura,
1968
B.napus genome was transferred into the back round of R.sativus
(mst) through intergeneric crosses followed by back crossing with
B.napus.
CMS seedling under low temperature showed chlorosis , because
chloroplast of R.sativus is sensitive to cold, it is governed by cp-
DNA , but mst is governed by mt DNA.
Protoplast fusion of R.sativus with B.napus carried out to have
normal green plants with ogu CMS characterisitics
This system now has been used for developing alloplasmic male
sterile line in B.juncea and B.campestris.
80. Genetic Male Sterility
•GMS is governed by two genes either recessive or dominant
genes(Kaul,1988)
•One more dominant gene is associated with development of
male sterility in B.napus type by means of transgenic male
sterility
Chemical Male sterility
1. Enthrel – Brassica juncea
2. Zinc methy arsenate- B.napus
3. GA- B.oleracea var capitata
91. Male sterility system in Safflower hybrid seed
production
•Presently genetic male sterility (GMS), cytoplasmic male sterility
(CMS) and thermo sensitive genetic male sterility (TGMS) lines are
available in India.
•Development of agronomically superior genetic male-sterile lines in
safflower in India have resulted in the development and release of
spiny safflower hybrids DSH-129 and MKH-11 in 1997 and NARIH-15 in
2005, the first non-spiny hybrid safflower NARI-NH-1 in 2001.
92. Male sterility system in Sunflower hybrid seed
production
Genetic Male sterility (GMS)
A. Complete male sterility
ms1-ms5 = male sterility in sunflower recessive gene
Two types of g-mst
i. Type 1-gmst-Bloomington type
ii. Type 2-gmst-Modern type
Cultivated Sunflower variety Karlik-68(Dwarf 68)- two recessive
genes msi1,msi2 (Stable and complete male sterile)
B. Partial male sterility –p mst
93.
94.
95.
96.
97.
98.
99. Male sterility system in Cotton hybrid seed
production
All three types of male sterility occurs (g mst,c mst,gc mst) in cotton
Genetic Male Sterility (GMS):
1. Reported in upland, Egyptian and arboreum cottons.
2. In tetraploid cotton, male sterility is governed by both recessive and
dominant genes.
3. However, male sterility governed by recessive genes is used in
practical plant breeding
4. Sixteen different genes in tetraploid cottons (13 in G. hirsutum and 3
in G. barbadense) and two in G. arboreum have been identified for
genetic male sterility.
5. Sterility is conditioned by dominant alleles at five loci viz, MS4, MS7,
MS10, MS11 and MS12 by recessive allele at other loci viz. msl, ms2,
ms3, ms13, ms14 (Dong A), ms15 (Lang A) and ms16 (81 A).
6. G. hirsutum line Gregg (MS 399) from USA is the basic source of
GMS possessing ms5 ms6 gene for male sterility.
102. CMS System
•In case of CMS, the originally discovered CMS sources involving G.
arboreum and G. anomalum cytoplasmic systems having interaction
with ms3 locus were not found effective or stable under different
environments.
•The only stable and dependable CMS source under varied
environment was developed through the utilization of G. harknessii.
The complete genome of G.hirsutum was transferred into the G.
harknessii cytoplasm.
•A single dominant gene ‘Rf’ from G.harknessii is essential for
fertility restoration.
•Fertility enhancer factor 'E' for this CMS restorer system was
obtained from a G.barbadense stock.
•The harknessii system is reported to contribute to good agronomic
properties and attraction to honey bees.
104. Mutation
G. arboreum, the first spontaneous male sterility mutant was
identified in variety DS-5
Chemical based male sterility
•FW 450(Sodium B-Dichloro-iso-butyrate)
•MH-30 (Maleic hydrazide)
•Ethidium bromide
Male sterility based hybrid Production
•GMS system. CPH2 (Suguna), First hybrid based on GMS released
at CICR, RS, Coimbatore
•G. harknessii based cms with fertility restoration gene sources
were used in developing the hybrid CAHH 468 (PKV Hy-3).
105.
106.
107.
108. Male sterility system in Potato hybrid seed
production
Inter-specific Hybridization
109. Chemical mutagens
Development of Male sterility
1. FW 450(Sodium B-Dichloro-iso-butyrate)
2. MH-30 (Maleic hydrazide)
3. Ethidium bromide
Genome transfer
S cytoplasm is in the genome of fr genes
Unreduced Gamete Production
S.tuberosum (2x) × S.tuberosum (4x)
Protoplast Fusion
S cytoplasm is retained