This document discusses molecular breeding techniques using the Barnase-Barstar system for inducing male sterility in plants. It explains that the Barnase gene is cytotoxic and kills tapetum cells, preventing pollen development and resulting in transgenic male sterility. The Barstar gene provides fertility restoration. The system has been used successfully in tobacco and oilseed rape to develop hybrid seeds. Some benefits of this system include efficient fertility restoration, easy maintenance of male sterile lines, and elimination of male fertile plants from lines. However, alternative systems that are more attractive than Barnase-Barstar have also been explored.

2. SUBMITTED BY
VIKAS KUMAR SINGH
M. SC. (AG), III rd SEM
DEPARTMENT OF GENETICS & PLANT
BREEDING,
CHAUDHARY CHARAN SINGH
UNIVERSITY, MEERUT
SUBMITTED TO
DR. S. S. GAURAV
ASSO. PROFESSOR,
DEPARTMENT OF GENETICS&
PLANT BREEDING,
CHAUDHARY CHARAN SINGH
UNIVERSITY, MEERUT
Heterosis and Its Exploitation

3. Contents Introduction
Features Of Markers
General Steps in MAS
MAS Breeding Scheme
Current status of molecular breeding
Classification of Marker
Achievements

4. Markers

5. Classification Of Markers
Molecular
Markers
Biochemical
Markers
DNA Based
Markers
Morphologic
al Markers
 Leaf tip
necrosis
 seed coat
color
 Isozymes
 SSR
 SNP
 RFLP
 RAPD etc.

8. Flanking
marker
Gene of
interest

9. Features
Marker A
QTL
5 cM
RELIABILITY FOR
SELECTION
Using marker A only:
~95%
Marker A
QTL
Marker B
5 cM 5 cM
Using markers A and B:
~99.5%

10. 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8
RM84 RM296
P1 P2 P1 P2
Not polymorphic Polymorphic!

11. Introduction
or
Marker assisted selection

12. Prerequisite for using MAS

13. General Steps in MAS

14. Overview of
‘marker
genotyping’

15. F2
P2
F1
P1 x
ResistantSusceptible
MARKER-ASSISTED SELECTION (MAS)

16. F2
P2
F1
P1 x
PHENOTYPIC SELECTION
DonorRecipient

17. Variety of approaches MAS

18. Marker-assisted backcrossing
MAB

19. 1 2 3 4
Target
locus
1 2 3 41 2 3 4
BACKGROUND
SELECTION
TARGET LOCUS
SELECTION
FOREGROUND
SELECTION
BACKGROUND
SELECTION

20. P1 x F1
P1 x P2
BC1
VISUAL SELECTION OF BC1
PLANTS THAT MOST CLOSELY
RESEMBLE RECURRENT PARENT
BC2
P1 x F1
P1 x P2
BC1
USE ‘BACKGROUND’ MARKERS TO SELECT
PLANTS THAT HAVE MOST RP MARKERS AND
SMALLEST % OF DONOR GENOME
BC2

21. Pyramiding

23. ACHIEVEMENT OF MARKER ASSISTED SELECTION

36. REASON FOR LOW IMPACT AND FUTURE NEEDS FOR MAS

37. Fact About molecular breeding…….

38. Barnase-Barstar System
Contents Introduction
Mechanism of Barnase-Barstar system
Fertility Restoration System
Research articles on this topic….
Features
Achievements

39.  For producing Dominant GMS.
 Need of effective fertility restoration systems.
 An effective restoration system is available in at least one
case, Barnase/Barstar system
Recombinant DNA techniques have made it possible to engineer new
systems of male sterility by disturbing any or number of developmental
steps specifically required for the production of functional pollen within
the microspore or for the development of any somatic tissues supporting
the microspores.

40. Tapetum Tissue

41. Bargene
Mariani et al. in 1992
Barstar
110 bp
long.

42. Induced GMS
Barnase gene is
cytotoxic killing the
tapetul cells, thus
preventing pollen
development result
transgenic male
sterility.

43. Each grandparent
has each part of
Barnase.
Bn3 : 3’ portion of barnase gene.
Bn5 : 5’ portion of barnase gene.

44. Two-Component System

45. Fertility restoration
Barstar
Mariani et al. in 1992
Barstar 89
bp long.

51. Selected transgenes used for production of male sterility
TRANSGENE SOURCE TRANSGENIC PLANT
barnase Bacillus amyloliquefaciens Tobacco, B.napus
Rnase T1 Aspergillus oryzae Tobacco, oilseed,rape
Bcp1 Brassica campestris B.oleracea
rolC A.rhizogenes Tobacco,potato,

52.  The transgenic hybrid rapeseed-mustard was developed by
multinational Proagro Seed Company Ltd. located at Gurgaon
(now a part of Belgium based Aventis crop science) large scale
field trials in year 2001-2002,this hybrid mustard gave 25% yield
advantage, but could not be cleared by GEAC for commercial
sowing at the farmer fields in October 2002.
 Another effort by Delhi University South Campus.

53.  Efficient fertility restorer system
 Easy maintenance of male sterile lines
 Easy elimination of a male fertile plants from male sterile lines
 Lack of adverse affects on other traits
 Stable male sterile phenotype over different environments

56.  They illustrated several approaches for inducing
male sterility. like-

58. Most Attractive than Barnase
Barstar system
Banga et. al.
B. oleracea

60. 1. Gupta P.K., Langridge P, Mir R.R.(2010)Marker assisted wheat
Breeding:present status and future possibilities,
2. Article shared by Sudhadip Mondal MAS meaning application
step achievements,
3. Journal of Drug Metabolism&Toxicology(review),
4. Singh,B.D. Plant Breeding Principles and Methods,
5. Marker-assisted selection:an approach for precision plant
breeding in the twenty-first century-Bertrand C.Y Collard and
David J Mackill,
6. Singhal.N.C,Hybrid Seed Production,
7. Internet&SlideShare etc
References:-