Formation of low mass protostars and their circumstellar disks
Male sterility
1. Chairman: Dr.V. Anbanadan
Asst.professor
Dep. Of Genetics and Plant Breeding
Co. Chairman: Dr. R.Esawaran
Asst.professor
Dep. Of Genetics and Plant Breeding
Co. chairman: Capt. Dr. R.Kanagarajan
Asst.professor
Deparment Of Entomology
3. Content
Male sterility
History of male sterility
Manifestation of male sterility
Importance of male sterility
Anther and pollen formation
Types of male sterility
Cytoplasmic male sterility
Genetic male sterility
Cytoplasmic genetic male sterility
Transgenic male sterility
Chemical induced male sterility
4. Male sterility is defined as the failure of
the plants to produce functional pollens
or male gametes.
5. History
Male sterility was first came in 1763 reported by
Koelreuter.
The first case of male sterility was reported by
Justus and Leinweber in 1960 in upland cotton
(Gossypium hirsutum L.).
Male sterility systems have been also developed
through genetic engineering (Williams et al. 1997)
Male sterility were artificially induced through
mutagenesis (Kaul 1988).
6. Genic male sterility has been reported in
cabbage (Rundfeldt 1960), cauliflower
(Nieuwhof 1961).
The first report of cytoplasmic male sterility
in rice was documented in 1954 by
Weeraratne et al.
A variety of genic male sterility has been
discovered in recent years, which includes
recessive and dominant genic male sterility
(Shi and Deng 1980; Yan 1989; Li et
al.1999).
7. Manifestation
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
8. Importance :
Hybrid production requires a female plant in
which no viable gametes are borne.
Emasculation is done to make a plant devoid
of pollen so that it is made female.
Genetic male sterility is used in hybrid seed
production but has limitations due to the
need to maintain female parent lines as
heterozygotes & segregation of fertile &
sterile plants each generation.
9. Anthers and pollen formation :
The development of anthers can be divided into
two phases :
Phase-I
Histospecification takes place, the morphology
of the anthers is established , cells and tissue
differentiation occurs.
Microspores and mother cells undergoes meiosis
At the end of Phase I, the anthers contain most of
its specialized cells and tissues, and tetrads of
microspores are present with in the pollen sacs.
10. Phase II:
A cell degeneration and dehiscence program is
executed when pollen grains differentiate.
The anthers enlarges and is pushed upward in the
flower by filament extension.
Tissue degeneration dehiscence and pollen grain
release occurs.
The cellular process that regulate anther cells
differentiation, establish anther tissue patterns,
It causes the anther to switch from Phase I to
Phase II are not fully known.
Cell differentiation and dehiscence events occurs
in a precise chronological order that can be
correlated with floral bud size.
11.
12. Types of male sterility. Male sterility in plants
can be controlled by nuclear genes or cytoplasm
or by both. Therefore, broadly there are atleast
three different mechanisms for control of male
sterility in plants.
1. Cytoplasmic male sterility
2. Genetic male sterility
3. Cytoplasmic genetic male sterility
4.Transgenic male sterility
5. Chemically induced male sterility
13. Cytoplasmic male sterility:
It occurs due to the involvement of non-
nuclear genes.
This type of male sterility is determined
by the cytoplasm. Since cytoplasm of the
zygote comes from the egg cell, the
progeny of such male sterile plants will
always be male sterile.
This type of male sterility is of
importance in certain ornamental species
where the vegetative part is of economic
value.
14. cytoplasmic male sterility are located in
mitochondrial DNA (mtDNA) in three male sterile
cytoplasms (T,C and S) and male fertile(N) cytoplasm.
It was found that mtDNA’s were differ in four
cytoplasm.
When chloroplast DNA is similar, if any difference
were found between four types of ctDNA. It proves
that CMS in higher plants associated with mtDNA
The mtDNA is associated with disease susceptibility
with CMS, both leaf blight and yellow leaf blight are
called as ‘HOST SPECIFIC TOXINS’.
The restorer genes help restore fertility through their
action on mitochondria.
15. The t cytoplasm cells in culture were treated
with toxins and resistant cells were selected.
Then mt of these resistant cells unaffected by
toxins. It could be shown that this change
involved in change in mt.
Several proteins are synthesized under the
control of mtDNA include cytochrome oxidase,
cytochrome b and ATPase these affected in
cytoplasm.
In microsprogensis the anther of T and N
cytoplasm, mitochondria degeneration was
observed in tapetum and middle layer of anther
at tetrad stage in T-cytoplasm and not in N-
cytoplasm
16.
17. Maternal inheritance of cytoplasmic
male sterility in plants
Inheritance of cytoplasmic male sterility and
restoration of fertility due to restorer gene.
18. CMS Line Developed
At
Elite line
converted
Origin of
elite line
IR 46826A IRRI IR 10154-23-3-3 IRRI
IR 46827A IRRI IR 10176-24-6-2 IRRI
IR 46828A IRRI IR 10179-2-3-1 IRRI
IR 46829A IRRI IR 19792-15-2-3-3 IRRI
IR 46831A IRRI Jikkoku Seranai 52-37 India
IR 46883A IRRI MR-365 India
IR 46885A IRRI PAU 269-1-8-4-1-1-1 India
MadhuA CRRI ,India Madhu India
HR 7017A Iri Korea Samkangbyeo Korea
Source: Ram H., H.(2012). Crop Breeding and Biotechnology. Chapter 2,96-98.
19. Genetic male sterility
GMS has been reported in about 175 plant species
(Kaul, 1988)
this type of male sterility is controlled by the gene(s)
from the nuclear compartment.
Genetic male sterility is ordinarily governed by a
single recessive genes, ms, but dominant genes
governing male sterility are also known, e.g., in
safflower.
Male sterility alleles arise spontaneously or may be
artificially induced.
A male sterile line may be maintained by crossing it
with heterozygous male fertile plants. Such a mating
produces 1:1 male sterile and male fertile plants.
20.
21. Types of genetic male sterility
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
2. PGMS
22. TGMS:
sterility is at particular temperature e.g. In rice TGMS line
(Pei- Ai645) at 23.30 C (China).
TGMS at high temperature is due to failure of pairing of two
chromosomes at metaphase was evident.
This abnormality led to abnormal meiosis, abnormal or
sterile pollens.
Anthers were shriveled and non-dehiscence-Male sterile.
The TGMS lines needs cool climate for seed setting ie., day
temperature should be < 240 C and night temperature should
be >180 C. This type of climate prevailed only in Gudalur of
Nilgiri District in Tamil Nadu.
24. 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
25. Hybrid Parentage
Hunan Pei ai 64s x Tequing
Anhui 7001s x Xiusui 04
Hubei 7001s x 1514
Guangdong Pei ai 64s x Shuanging11
Sichuan Pei ai 64s x Shuangingyou 1
Source: Ram H., H.(2012). Crop Breeding and Biotechnology. Chapter 2,100.
26. Cytoplasmic- Geneic male sterility
In this system, male sterility is expressed by
homozygous recessive gene in presence of sterility
cytoplasm and fertility is restored by dominant
allele in presence of fertile as well as sterile
cytoplasm.
In this system, a variety having sterile cytoplasm
(S) and recessive homozygous (rr) genes, is used
as seed parent and is known as 'A' line.
In maintainer line ‘B‘, gene present are recessive
(rr), but the cytoplasm is male fertile (F), whereas,
in restorer, dominant gene (RR) are present, but the
cytoplasm may be fertile or sterile.
27.
28. Transgenic male sterility
The expression of bacterial cytotoxic ribonuclease
(Barnase) in the male reproductive organ of the
female parent line and fertility restoration by
ribonuclease inhibitor (Barstar) delivered by the
male parent.
Tapetal degeneration is a programmed cell death
(PCD) event with typical cytological features of cell
shrinkage, mitochondria and cytoskeleton
degeneration, nuclear condensation,
oligonucleosomal cleavage of DNA, vacuole
rupture, and endoplasmic reticular swelling.
29. It is desirable to develop a hybrid seed system
that is equipped with capabilities of complete
pollen abortion in a biologically safe and tightly
controlled manner, as well as efficient male
fertility restoration in the F1 hybrid.
A transcription regulation system for male
sterility–fertility restoration in plants
It includes two tapetum-specific expression
cassettes; one expressed in the female parent and
the other expressed in the male parent of the
desired F1 progeny.
Arabidopsis BECLIN1 which generates the
complete male sterile parent by altering the
tapetal degeneration program.
30.
31. Chemical male sterility
which kill the male gametes, spores or organs
and render the treated plant male sterility. These
chemicals are known as male-gametocides or
chemical hybridizing agents and the selective
abolition of male sex is termed chemical male
sterility (chemical male sterility).
35. Hybrid Parentage
APRH- 1 IR 58025 A xVajram
APRH-2 IR 62829 A x MTU9992
MGR- 1 IR 62829 A x10198-66-2R
KRH-1 IR 58025 A x IR9761-10-IR
CNRH-3 IR 62829 A x Ajaya R
DRRH-1 IR 58025 A x IR40750-82-2-2-3R
KRH-2 IR 58025 A x KMR3
Pant Shankar Dhan 1 IR 58025 A x UPRI192-133R
CORH 2 IR 58025 A x C 20R
ADTRH 1 IR 58025 A xIR66
Sahyadri IR 58025 A x BR827-35-3-1-1-R
Narendra Sankar Dhan 2 IR 58025Ax NDR 3026-3-I-R
Source: Ram H., H.(2012). Crop Breeding and Biotechnology. Chapter 2,96- 98.
Hybrids developed using CMS in India
36. Hybrid Parentage
HB1 Tift 23 A x BIL3B
HB2 Tift 23 A xJ88
HB3 Tift 23 A XJ104
HB4 Tift 23 A x K560
HB5 Tift 23A x K559
Source: Ram H., H.(2012). Crop Breeding and Biotechnology. Chapter 6,187-209.
Hybrids in Bajra
37. • Armavirtsky 3497
• BSH1
• BSH2
• BSH3
• BSH4
• BSH5
• BSH6
• BSH8.
• Out of this BSH 1 and BSH2 found to be promising hybrids
for seed production.
• First Sunflower hybrid BSH1 was released in 1980 by UAS
Bangalore.
Hybrids developed Using CGMS
system in Sunflower
Source: Ram H., H.(2012). Crop Breeding and Biotechnology. Chapter 16,395- 407.