Pre-breeding involves introducing beneficial genes from exotic or wild plant materials into domestic crops to broaden their genetic base. It captures useful traits and puts them into forms usable for breeding programs. The document discusses pre-breeding strategies like backcrossing, convergent improvement, and bridge crosses. Pre-breeding has enhanced disease resistance and drought tolerance in crops like maize, pearl millet, and sorghum. While it provides long-term benefits, pre-breeding also faces challenges like linkage drag and hybrid sterility. Overall, pre-breeding is important for generating genetic diversity and new traits to develop improved crop varieties.

2. CREDIT SEMINAR ON
PRE BREEDING FOR CROP IMPROVEMENT
Speaker
Bharat Lal Meena
Ph. D. (PBG)
DEPARTMENT OF PLANT BREEDING AND GENETICS
COLLEGE OF AGRICULTURE, UMMEDGANJ FARM, KOTA
( AGRICULTURE UNIVERSITY, KOTA)
Major Advisor
Dr. N. R. Koli
Associate Professor
Seminar Incharge
Dr. B. L. Dhaka
Assistant Professor

3. INTRODUCTION
The term "enhancement" was first used by Jones (1983).
According to him it can be defined as transferring of useful
genes from exotic or wild types into agronomically acceptable
background.
Rick (1984) used the term pre-breeding or developmental
breeding to describe the same activity.
The pre-breeding consists of identifying a useful character,
capturing its genetic diversity and putting those genes into
usable form.

4. What Is Pre -Breeding?
(The Global Crop Diversity Trust) Pre-breeding is the
art of identifying desired traits and incorporation of
these into modern breeding materials.
 Pre-breeding offers a unique opportunity by
introgression of desirable genes from wild germplasm
into cultivated background with minimum linkage drag.
Pre–breeding is an early phase of any breeding
programme utilization wild germplasm and is also
called as Developmental breeding or Germplasm
enhancement.

5. Objectives
Improved germplasm and associated genetic
knowledge that enhance resistance expression
and diversity.
Reduced uniformity in crops
Identification of desirable traits/genes and their
subsequent transfer into suitable set of parent
for further selection.
Improved parental stocks.
Identify of potentially useful genes in well
organized and documented gene bank.

6. Why pre-breeding is important
Search for new genes/traits for better adaptation
due to change in climate.
Evolving pest & pathogen population and
motivating plant breeders to look for new source of
in gene bank.
Its most promising alternative to link genetic
resources and breeding programmes.
It will also help in value addition of different
genotypes through genetic enhancement In
improving the level of resistance to biotic and
abiotic stress.

7. Need for Pre-Breeding / Genetic Enhancement
 To meet the market requirement, plant breeders have to
develop improved cultivars, which needs elite breeding
material. Pre- breeding is valuable for this purpose.
 In the past, more attention has been given to adaptation
and performance through selection than to generation of
new variability to fulfill immediate needs.
 Crop improvement has led to narrowing down of genetic
base due to slower progress in plant breeding and
increased risk of genetic vulnerability. pre-breeding is
required to enhance the value of germplasm.

8. WHAT IS GENE POOL ?
A gene pool consists of all the genes and their alleles present in all such
individuals, which hybridized or can hybridized with each other.
It includes all cultivated cultivars, wild species and wild relatives.
GP2 GP3
PRIMARY GENE POOL SECONDARY GENE POOL TERTIARY GENE POOL
Intermating is
easy Leads to
production of
fertile Hybrids.
It includes plants
of the same
or closely related
spp.
The genetic materials
That leads to partial
Fertility on crossing
with GP1
It includes plants
belongs to Related
species.
The genetic materials which
leads to production of Sterile
hybrids on crossing with GP1.
Transfer of genes from such
materials to GP1 is possible
with the help of special
breeding techniques.
Genepool for Genetic Enhancement
GP4
QUATERNARY GENE POOL
Unrelated plant
species and/or
other organism

9. Pre‐breeding strategies
Pre-Breeding
Gene Bank Pre-Breeding Breeding
Collection
Maintenance Evaluation
Varietal
improvement
Varietal
release
Characterizatio
n
Characterizatio
n
Parental
development
Parental
development

12. Pre-breeding as a bridge between genetic resources and
crop improvement.

13. Main Points Related to Pre-Breeding/Genetic
enhancement
1.Main purpose - Genetic enhancement is carried out for
broadening the genetic base of the population. It
increases genetic diversity in the population.
2. Main Steps – three main steps
a) Identifying a useful character,
b) Capturing its genetic diversity and
c) Putting those genes into usable form.
3.Base Material –Materials viz. agronomic base, exotic
germplasm, wild species and unrelated species.
4.Breeding Method used – the backcross method widely
used . Now biotechnological approaches are also used
for genetic enhancement.

14. 5.Impact – the major impact of genetic enhancement is
value addition in the germplasm
6.End product – the end products of genetic enhancement
programme are improved germplasm line which can be
used as parents for developing productive cultivars/
hybrid in traditional breeding.
7.Time Frame – the genetic enhancement is a long term
programme as compared to traditional breeding.
8.Under taken by – the genetic enhancement work is
under taken by public sector plant breeding
organization.

15. 9.Phase of Breeding - Pre-breeding is the early
component of sustainable plant breeding which refers
to the transfer of useful gene and gene combinations
from non- adapted sources into breeding material
mainly consists of exotic germplasm and wild species/
relatives of the crop plants.
10.Adaptation – pre- breeding helps in improving the
genetic adaption of the populationirstly by creating
genetic diversity and secondly by broadening the
genetic base of the population.

16. PRE-BREEDING v/s TRADITIONAL BREEDING
S.N. PRE-BREEDING TRADITIONAL BREEDING
1. It is also known as genetic
enhancement
It is also known as sustainable plant
breeding.
2. It leads to genetic enhancement of
germplasm.
It leads to development of productive
cultivars/hybrid.
3. It leads to broadening the genetic
base of the population.
In improved cultivars the genetic base
become narrow.
4. It leads to value addition. It does not lead to value addition.
5. The chief breeding method is
backcross method.
All breeding method such as
introduction, selection, hybridization
and mutation are used.
6. The end products are improved
germplasm lines.
The end product is cultivar or hybrid.

17. 7. The end product is used as
parent for developing
improved cultivar hybrid.
The end product is used for
commercial cultivation.
8. It involves adapted and non-
adapted genotypes in
crossing programme.
It includes only adapted genotypes.
9. It is a long term breeding
programme.
It is a short or medium term
breeding programme.
10. It is taken up by public sector
plant breeding organizations.
It is taken by both public and private
sector organizations.

18. Methods of Genetic Enhancement
1. Backcross method :-
backcross refers to crossing either of its parents.
Backcross is widely used for introgression and
incorporation of desirable gene from exotic germplasm
and wild species into well adapted cultivars.
 Introgression - To transfer of one or a few allele from
exotic stocks to adapted breeding populations.
 Incorporation -Incorporation refers to a large scale
programme aiming to develop locally adapted
population using exotic / un-adapted germplasm.

19. :
 Main points about backcross method
a. It used for genetic enhancement of both self and cross
pollinated species.
b. It is used for transfer of both oligogenic and polygenic
traits.
c. In this method , cultivated variety or adapted variety is
used as maternal parent and the exotic germplasm or un-
adapted line as donor parent. The recipient parent is also
known as recurrent parent because repeated backcrossing
is done with recipient parent.
d. Generally 5 to 6 backcross are sufficient for transfer of a
character.

20. 2. Convergent Improvement
 In this method two genotype say A and B are
selected for crossing. The crossing is done between
these genotypes and the F1 is backcrossed to both
A and B parents.
 The main objective of this scheme is to improve
both the lines simultaneously.
The desirable character of A is transferred to B and
vice-versa.
 This method is used when each of the two parent
is deficient in one character which is present in the
other parent.

21.  Main features of this method are –
1.Each parent is deficient in a character is present
in other parent.
2.It is simultaneously improves two populations.
3.It can be used for self and cross pollinated
species.

22. 3. Bridge Cross
Bridge cross is used when the hybrid between
cultivated species and wild species is sterile in a
backcross programme and this does not permit
the transfer of character from the donor to the
recipient species.
An example of pre breeding through bridge
cross is the use of synthetic N. digluta for the
transfer of resistance to tobacco mosaic virus
from N. sylvestris to N. tobacum.

23. 4. Biotechnological Approaches
The transfer of genes for various aspects viz.
insect resistance , virus resistance, herbicide
resistance, quality traits etc. From unrelated
species or even from unrelated organism into
easily crossable genetic background also comes
under pre-breeding. i.e. Bt-cotton

24. GermplasmCollection
• A Germplasm collection of a crop species consists of
a large number of lines, varieties and wild species of
the crop. such collection are also called gene banks.

25. ORGANIZATIONS ASSOCIATED WITH PLANT GERM PLASM
INTERNATIONAL ORGANIZATIONS:
1. Consultative Groups For International Agricultural Research
(CGIAR)
2. International Plant Genetic Resource Institute (IPGRI), Rome,
Italy.
3. International Potato Centre (CIP), Lema,Peru.
4. IRRI,Phillipines.
5. ICRISAT, Hyderabad ,India
NATIOANAL ORGANIZATIONS :
1. NBPGR,Pusa ,New Delhi
2. CRRI, Cuttack, Odisa etc.

26. Practical Achievements
a. Maize: In maize new inbred lines have been developed
through pre- breeding which are used as parents for
development of productive single cross hybrid. These
single cross hybrid are superior to double cross hybrid.
b. Pearl millet : Introgression of heat and drought
tolerance and blast resistance from Pennisetum
violaceum.’
c. Sorghum: Incorporation of Ethiopian, Sudanese land
race traits into adapted Indian cultivars has been done.

27. d. Sugarcane: Pre-breeding has resulted in development
of inter-specific genetic stocks of S. spontaneum, S.
sinense and S. officinarum.
e. Barley : In barley, pre- breeding has resulted in
creating vast genetic diversity and broadening the
genetic base of breeding populations.
f. Cotton : in cotton, fiber quality parameters and
resistance to biotic ad abiotic stresses have been
introgressed from wild species.
Genetic enhancement has also been achieved in cassava,
oilseed, lentil, tomato, chickpea, etc.

28. Advantages of Pre-Breeding
 The genetic diversity has depleted in the improved cultivars.
Genetic enhancement is useful in restoring genetic diversity
in such cultivars.
 It helps in combining useful genes or gene combination from
landraces, and wild species into the cultivated or well
adapted genotypes. such traits include, resistance to biotic
and abiotic stresses, earliness and improvement in quality
parameters.
 It also leads to creation of new genetic variability in various
economic traits. Thus it leads to value addition in the
germplasm.
 It helps in broadening the genetic base of the population
which is essential for achieving stability in yield over regions
and seasons.

29. Problems associated with Genetic
Enhancement
 Both technical and financial challenges.
Long duration, temperature and photoperiod
sensitivity of wild species.
Cross incompatibility in inter-specific crosses.
 Linkage drag.
 Hybrid inviability and hybrid sterility.
 Small sample size of inter-specific hybrid
population.
 Lack of availability of donors for specific traits viz.
resistance to diseases and pests.

30. Pre-Breeding: Present Status and Future
 Limited genetic variability in cultivated germplasm blazed
pre- breeding in most crop improvement programs
 New gene pools, useful genes, wider adaptability,
broader genetic base for agronomic and nutrition-related
traits, as well as for resistance/tolerance to important
biotic/abiotic stresses
 Phenotyping and genotyping in identifying the lines with
enhanced genetic base and minimum linkage drag for
use in future breeding programs, as well as to find out
the markers associated with traits of interest

31. Concluding remarks
 Sufficient diversity in the form of landraces and wild
relatives
 Several useful genes for cultivar improvement, utilization of
in breeding programs
 Pre-breeding activities be initiated to generate new
PGR [promising landraces and wild relatives for
breeders]
 Useful variability for breeding pipeline to develop new high-
yielding cultivars, resistant to stresses and broad genetic
base
 Novel techniques for pre-breeding [5–10 years]

32. Thank You