male sterility

1. PRESENTATION
ON
MALE STERILITY
&
IT’S ROLE IN AGRICULTURE
Submitted to: Submitted by:
Dr. A. K. Sharma Sanjay Kumar Sanadya
professor M.Sc. (PBG) 1st year

2. INTRODUCTION
Discovery:- Keolreuter (1763) in flowering plants.
Definition:-
• Male sterility refers to a condition in which pollen is either absent or
nonfunctional in flowering plants.
• FEATURES OF MALE STERILITY
• Permits allogamy.
• Leads to heterozygosity.
• Occurring naturally by spontaneous mutations as well as artificially by chemical or
physical mutagens.
• Governed by nuclear genes, cytoplasmic genes, or both.
• Caused due to pollen or anther abortion.

3. TYPES OF MALE STERILITY
A. GENETIC MALE STERILITY (GMS)
(1) TEMPERATURE-SENSITIVE GENETIC (TGMS)
(2) PHOTOPERIOD-SENSETIVE GENETIC (PGMS)
(3) TRANSGENIC GENETIC MALE STERILITY
B. CYTOPLASMIC MALE STERILITY (CMS)
C. CYTOPLASMIC GENETIC MALE STERILITY (CGMS)
D. CHEMICALLY INDUCED MALE STERILITY

4. 1.GENETIC MALE STERILITY (GMS)
Caused by nuclear genes is called genetic male sterility.
Reported in several plants like wheat, barley, cotton, pigeonpea, tomato,chillies etc.
Feature of GMS:-
•GMS is mainly governed by a monogenic, recessive gene but rarely oligogenic,
dominant.
In this system consists of two type line, viz. A line & B line.
A line:-
It is male sterile line which is used as female parent in hybrid seed production. It is
represented by mm (homozygous recessive).
B line:-
It is a male fertile line which is used to maintain male sterility in A line. Also called
maintainer line. It is represented by Mm (heterozygous dominant).
Both A & B lines are isogenic lines with a differences only on fertility/sterility locus.

5. MAINTENANCE OF MALE STERILE LINE
Maintained by Sib mating between F1
progeny with their male sterile A line.
Such cross will produce F2 progeny in
which 50% sterile plants and 50% fertile
plants.
• Male sterile plants are used as female
parents in hybrid seed production.
• Male fertile plants are rouged out.
INHERITANCE OF GMS

6. 1.TEMPERATURE- SENSITIVE GMS
Sterility influenced by temperature is called temperature-sensitive GMS.
GMS can sometimes become fertile at low temperature.
Examples-
• In rice, the sterile plants produced by the male sterile gene at above
230C temperature and become fertile below 230C.
• In cotton, below 120 C sterile plants become fertile.
2. PHOTOSENSITIVE-GMS
Sterility influenced by day length conditions is called photosensitive-
GMS.
Example-in rice, long day condition leads to male sterility and short day
condition leads to male fertility.
This type male sterility is being used to developed hybrid rice in China.

7. 3.TRANGENIC GENETIC MALE STERILITY
Transgene is used for induction of male sterility.
It’s induced by technique of genetic engineering is called transgenic male sterility.
Examples:-tobacco, rapeseed, maize etc.
Features of transgenic male sterility
Source of gene- Bacillus amyloliquefacience
Types of genes involved-
• For hybrid seed production, Barnase and Barstar gene are involved. Barnase gene
causes male sterility & Barstar gene restore the fertility.
• Both genes are produced from the same bacterium.
Gene integration:-
• Barnase is integrated in any plant, called A line.
• Gene Barstar is integrated in restorer line, called R line.
• Thus, it is a two line system.
Nature of gene:-
• Transgenic male sterility controlled by a dominant gene called Barnase.
• The male sterile plants are always heterozygous.

8. Advantages :-
• Fertility restoration in the hybrid and crossing plans are relatively easy.
• Use in both seed propagated and vegetatively propagated crops.
• Less area and labour because maintain only two lines.
• Does not have undesirable agronomically characters.
Disadvantage :-
• Less stable due to GMS affected by environmental factors like temperature and day length condition.
• Increases cost of production of hybrid seed because 50% fertile plants are removed every year.
Utilization In Plant Breeding:-
GMS has been exploited commrcially in few country, in U.S.A. successfully used in castor.
In India, used pigeon pea hybrid ICPH8 by ICRISAT, Hyderabad, and public sector hybrids (CoH1, CoH2)
In chillies, line Ms12 has GMS allele ms-509 (through mutagenesis) which is used for hybrid seed
production in korea and hungary.

9. 2. CYTOPLASMIC MALE STERILITY (CMS)
This type of male sterility controlled by cytoplasmic gene.
Cytoplasm of a zygote comes from egg cell, the progeny of such plants would always
be male sterile.
• This system consists of A line and B line.
A line:-
It is male sterile line which is used as female parent in hybrid seed production.
B line:-
It is a male fertile line which is used to maintain male sterility in A line called maintainer
line & used as male parent.
• Cytoplasmic male sterile line maintained by crossing of A line with B line.
• CMS cannot be utilized for hybrid seed production without use of restorer line,
because F1 seed produce only male sterile plants.

10. Advantages:-
• Highly stable because not influenced by environmental conditions such as
temperature and day length.
• Less area requires, because the breeder has to maintains A & B line.
Disadvantages:-
• Cannot be used for developments of hybrids in these crops where seed is
economic product.
• It is impossible to restore fertility in hybrid due to governed by plasma genes.
• Sometimes, CMS line has inferior agronomic performance.
Utilization In Plant Breeding:-
But in these crops plants where seed is the economic part, it is used for production of
CMS line. Examples:-
In rice, CMS-WA,CMS-bo, CMS-CW
In pearlmillet , Tifton A1, ludiana A2
In maize, CMS-C CMS-S CMS-T
In sorgum, kafir 60

11. 3. CYTOPLASMIC GENETIC MALE STERILITY (CGMS)
First time reported by Jones and Davis in 1944 in onion.
Controlled by both plasma genes and nuclear genes, called cytoplasmic genic male
sterility.
Reported in both sexually propagated and asexually propagated species such as
pearlmillet, sorghum, cotton, maize.
This system includes A, B & R lines.
A line:-
It is male sterile line which is used as female parent in hybrid seed production.
B line:-
It is a male fertile line which is used to maintain male sterility in A line called maintainer
line.
R line:-
Which is used to restored male sterility in male sterile plant, used as male parent in
hybrid seed production.

12. A LINE
Male
sterile
(ms/ms)S
B LINE
Male fertile
(ms/ms)F
Male
sterile
(ms/ms)S
To maintain CGMS line by crossing of A line with B line.
In case of CGMS line, should have recessive genes in nucleus otherwise it would
become fertile.

13. Advantages :-
• Widely used for hybrid seed production in both seed propagated & vegatatively
propagated species.
• Highly stable and reliable.
• Not affected by environmental factors.
Disadvantages:-
• Its requires more area and labour, because the breeder has three types of material,
viz., A, B & R line.
• Moreover, sometimes CGMS line has inferior performance.
Utilization In Plant Breeding :-
CGMS can be successfully utilized for the development of commercial hybrids in both
seed propagated and vegetatively Propagated crops.
CGMS has been effectively used for commercial production of hybrids in maize,
sorghum, onion, sugarbeet, pearlmillet and other crops.

14. 4.CHEMICALLY INDUCED MALE STERILITY
Male sterility is originated due to mutagens or chemicals (gametocide) called
chemically induced male sterility.
By mutagens, male sterility is heritable & gametocide, induced male sterility is non-
heritable.
Ideal Gametocide Should Be:-
• induced male sterility without affecting ovule fertility.
• Economical and its method of application should be simple.
• Safe for use and minimum side effect on plant growth.
• Some gametocides such as NAA, Maleic Hydrazide, ethrel, Gibberellins,
Ethidium Bromide Etc.
• Utilization In Plant Breeding:-
• Ethidium Bromide has been used in Pearlmillet &Barley for induction of CMS.
• In china, chemically induced male sterile line have been used for hybrid seed
production.

15. Transfer Of Male Sterility:-
Generally 6 to 7 backcross are sufficient to transfer male sterility gene into the
background of a popular variety.
For transfer of male sterility, the adapted is use as male parent and male sterile
genotype as female parent.
• In case of CGMS line, should have recessive genes in nucleus otherwise it would
become fertile.
Limitations Of Male Sterility:-
I. Very difficult to identify the male sterile line before anthesis.
II. Cannot be used in these crops in which efficient natural pollen dispersal mechanism
is lacking and morphology is not suitable for cross pollination.
III. Moreover, sterile cytoplasm has adverse effects on yield components in some
crops.

16. TRANSFER OF
CGMS

17. HYBRID SEED PRODUCTION IN RICE
By Male Sterility :-
Rice being a self pollinated crop, requires the use of male sterile line to develop and
produce F1 hybrids.
Development of male sterile line for hybrid rice production.
CGMS
PGMS
TGMS
First hybrid rice developed by China in 1970 from CMS-WA line which is identified in
the population of O.sativa var.spontanea (wild rice).
Three line method involve in CGMS system with A line, B line & R line. A line
maintain by cross between A line with B line, when cross between A line with R line
produces a fertile F1 hybrid.

18. Hybrid rice varieties
Important varieties released from 1994 to onwards which is enlisted:-
variety year
Public sector
APRH 1 1994
APRH 2 1994
Pant Shankar Dhan 1 1997
CORH 2 1998
Private Sector
PHB 71 1997

19. HYBRID SEED PRODUCTION IN COTTON
By Male Sterilty :-
16 different genes found in tetraploid cottons (13 in G. hirsutum and 3 in G.
barbadense) and two in G. arboreum have been identified for GMS.
CGMS system has been developed in cotton for hybrid cotton production.
The CMS line AK32A has been derived by Transferring the cytoplasm of
G.harknesii into G.hirsutum. The restorer gene has been obtained from
G.harknesii.
CMS line has to be hand pollinated since there is little pollen dispersal.
The cost of seed production using the CMS system is expected to be only
10% of that by hand emasculation and pollination.
• Also produced hybrid cotton by genetic male sterility governed by two
recessive gene ms5 &ms6.
• Male sterile and restorer line are planted in 4:1 or 5:1 in same field.
• Seed Harvested from the male sterile plants.

20. Hybrid Cotton Varieties
Important varieties released are enlisted:-
Variety (year) Variety (year)
Suguna (1978) PKV HY5 (2000)
ANKUR 15(1983) PKV DH1 (2000)
MECH 11 (1984) G.COT MDH II
(2002)
MECH 4(1990)
PKV HY-3 (1993)
PKV HY-4 (1996)
ANKUR 09 (1997)

21. HYBRID SEED PRODUCTION IN PEARLMILLET
By male sterility:-
Pearlmillet is cross pollinated species, first hybrid pearlmillet was developed by PAU ,
Ludhiana in 1965 was HB1 based on CMS System using tifton23A introduced from tifton.
Variety VARIETY
HB1 MH 179
HB3 BJ104
HB5 PUSA 23
PHB10 HHB67
PHB11
BK560

22. Key references
Singh B.D. 2009 plant breeding principles and methods kaiyani publisher new delhi
Singh P. Essential of plant breeding

23. THANK YOU