This document discusses the history and development of hybrid vigor and heterosis breeding in crops. It begins with early observations of hybrid vigor in tobacco and other plants in the 18th and 19th centuries. The term "heterosis" was coined in the early 20th century to describe the increased vigor seen in hybrid offspring. Several hypotheses for the genetic basis of heterosis are described, including dominance, overdominance, and physiological theories. The document outlines the major steps in heterosis breeding, including developing inbred lines, evaluating combining ability, and producing hybrid seeds. Different hybrid types and seed production methods are discussed, with a focus on mechanisms exploited commercially like male sterility, self-incompatibility, and emasculation.

2. Introduction

3. Historical Background
Kolereuter (1766) hybrid vigour in tobacco
Darwin (1877) hybrids from unrelated plant types are
highly vigorous.
Beal (1880) higher yield of hybrids between open
pollinated varieties and advocated the cultivation of
intervarietal hybrids
Shull the term “heterosis” to the phenomenon where
F1 hybrid is superior to both the parents.
East and Hayes (1912) the term “heterozygosis” .

4. Hayes and Jones (1916) first suggested the
exploitation of heterosis in vegetable crops.
F1 hybrid eggplants were used at commercial scale
in Japan since 1925.
First report of hybrid vigor flashed at national level
by IARI in chilli during 1933.
First hybrid of bottle gourd “Pusa Meghdoot” in
1971 and after two years in 1973 hybrids of
summer squash (Pusa Alankar) and cucumber
(Pusa Sanyog) were developed.
Beginning of hybrid research persuaded private
sector under taking and Indo-American Hybrid
Seed Company released hybrids of tomato
“Karnataka” and capsicum “Bharat” in 1973 for
commercial cultivation.

5. Inbreeding
Inbreeding is mating between individuals
related by descent or ancestory.
 Selfing
 Sib-mating

6. Consequences of Inbreeding
 Increase in homozygosity
 Exposing recessive characters
 Fixation of genotypes
 Inbreeding depression
 Reduction in fitness
 Purification of types
 Increase in environmental variability
 Reduction in yield

7. Degree of Inbreeding
Depression
 High inbreeding depression
 Moderate inbreeding depression
 Low inbreeding depression
 No inbreeding depression

8. Homozygous and Heterozygous
Balance
 Cross fertilized species are highly heterozygous.
 The sum total of unfavourable recessive genes (lethal,
subvital and others) constitutes genetic load of these
species.
 Harmful effects are masked by dominant alleles.
 Genetic organisation favours heterozygosity -
Heterozygous balance.
 Self fertilized species are naturally homozygous.
 No genetic load.
 Genetic organisation is adapted to homozygosity –
Homozygous balance.

9. Terminology
Heterozygosis (East and Hayes, 1912)
Effective differences resulted in the increased vigour
or size in the cross-bred organism solely due to
heterozygous condition of the genes.
Heterosis (Shull, 1914 and 1948)
The increased vigour, size, fruitfulness, speed of
development, resistance to diseases and pests
manifested in cross-bred organism as compared to
corresponding inbred, as the specific result of
unlikeness in the constitution of uniting parental
gametes.
Heterosis(%)=F1-{(p1+p2)/2}×100
(p1+p2/2)

10. Hybrid Vigour (Jones, 1918)
Synonyms to heterosis.
Heterobeltiosis (Fonesca and Patterson, 1968)
The increased performance of the hybrid over the
better parent.
heterobeltiosis (%)= (F1-BP)×100
BP
Economic heterosis or Standard heterosis
The heterosis in relation to the best commercial
variety of the crop.
Euheterosis (Dobzhansky, 1950)
True heterosis only when the hybrid possessed higher
fitness than the parents.

11. Positive and Negative Heterosis
(Powers,1944)
Inferior expression of the hybrid as a manifestation of
heterosis - negative heterosis
Superior expression of the hybrid – positive heterosis
Several Other Terms
Adaptive heterosis (Dobzhansky, 1950)
Selective heterosis (Mac Key, 1926)
Labile heterosis (Mac Key)
Fixed heterosis
Luxuriance (Dobzhansky, 1950)
Extreme heterosis for most of the morphological
characters but adaptively inferior, i.e., absence of heterosis
for fitness.

12. Categories of Heterosis
• Intra-population heterosis
• Inter-vareital heterosis
• Inter-specific heterosis

13. Sources of Heterosis
(Hayes and Foster)
 Complementary interaction of
additive, dominant or recessive
genes at different loci i.e., epistasis.
 The accumulated action of favorable
dominant or semidominant genes
distributed among the two parents
involved i.e., dominance.
 Favourable interaction between two
alleles at the same locus i.e.,
overdominance.

14. Manifestation of Heterosis
 Can be traced at:
 At molecular level
 At functional level
 At cellular level
 At the organism level

15. Manifestation of Heterosis
Expressed in following manner:
 Increased yield
 Increased reproductive ability
 Increase in size and vigour
 Better quality
 Earlier flowering and maturity
 Greater resistance to diseases and insect
pests
 Better adaptability

16. Hypothesis of
Heterosis

17. Genetic Basis of Heterosis
 Dominance hypothesis (Devenport, 1908;
Keeble and Pellow, 1910)
 Dominant alleles have favourable effects
 Recessive alleles have unfavourable effects
 In heterozygous stage, deleterious effects of
recessive alleles is masked by their dominant
alleles- heterosis.
Heterosis is due to accumulation of favourable
dominant genes, all acting in additive manner.

18.  Objections:
 It should be possible to select inbred homozygous
for all the beneficial dominant genes and such
individuals should have the same vigour as the F1
hybrid and also true breeding.
 Rejected by Jones (1917)- dominant and recessive
alleles being situated on the same chromosome shows
linkage and cannot be separated even with the high
frequency of crossover.
 The F2 population should show the skewed
distribution
 Rejected by Collins (1929)- the skewness because of
dominance is not great if the large number of factors are
involved in the expression of character.

19.  Overdominance hypothesis/ single gene
heterosis/ super-dominance/ cumulative
effect of divergent alleles (East and
Shull, 1908)
Heterozygote at atleast some of the loci
are superior to both the homozygotes i.e.
Aa > AA or aa
 Objection:
 Superiority of heterozygotes need not to be result
of overdominance due to linkage in repulsion
phase or epistatic effects.

20.  Physiological basis of heterosis
(Ashlay,1930)
 Heterosis results from the greater initial weight of the
embryo resulting from some process between
fertilization and maturation of seed.
 Hybrid vigour is nothing more than the maintenance of
initial advantage in embryo size.
 Hybrid do not differ from their parents in relative
growth rate.
 Three stages were studied:
 Seed and embryo development
 Early seedling growth
 Late growth

21.  Biochemical basis of heterosis
Several metabolic processes
Role of phytohormones
 Plasmic or organelle heterosis
Mitochondrial heterosis
Chloroplast heterosis
 Molecular basis of heterosis
More nuclear DNA
More polysomes
Increased DNA replication, translation,
transcription i.e. repeated RNA sequences.

22.  Heterosis in cross pollinated species
– Show heterosis when inbred lines are used as
parents.
– Commercially exploited in – onion, cucurbits,
cole crops.
 Heterosis in self pollinated species
– Show heterosis, but the magnitude is less
than that in the case of cross pollinated
species
– Commercially exploited in – tomato, brinjal,
etc.

23. Crop Total
Area(00
0’ha)
Share Open Pollinated Seed Share F1 Seeds
Area
000 ha.
Seed
Reqd
(Tons)
Value
(Rs.million)
F1 area
000ha.
Seed
Reqd.
(Tons)
Value
(Rs.
Million)
Beans
Brinjal
Cabbage
Capsicum
Carrot
Cauliflower
Chilli
Cucumber
Gourds
Muskmelon
Okra
Onion
Peas
Radish
Tomato
Watermelon
Others
260.60
533.50
274.00
75.00
168.00
306.90
627.30
212.00
448.00
125.50
390.00
428.00
257.00
212.00
549.00
137.00
1150.00
260.60
236.77
164.40
46.31
113.32
225.39
472.55
123.13
279.89
73.96
344.14
373.64
136.98
200.49
354.67
79.43
575.00
8756.16
75.06
82.20
22.00
804.54
146.05
197.76
223.48
1028.59
78.86
3974.86
4077.39
5475.82
3869.43
123.27
177.13
1437.50
218.90
16.51
57.54
11.00
160.91
73.03
59.33
89.39
257.15
23.63
238.49
244.64
164.27
967.36
59.17
70.85
359.38
-
101.47
109.60
24.94
5.96
39.77
52.51
30.78
49.39
15.15
16.22
0.00
0.00
4.09
190.98
42.77
0.00
-
16.91
18.27
4.16
19.88
9.94
8.75
25.65
82.32
7.57
67.57
0.00
0.00
27.28
22.28
35.64
0.00
-
67.65
164.40
83.13
198.80
99.44
175.02
128.26
249.96
37.87
54.05
0.00
0.00
136.39
334.21
142.57
0.00
Total 6154.3.0 4060.67 30550.00 3071.55 683.63 346.22 1868.74
Source: Agriculture Today ----FEBRUARY-2003----
Estimated Size of Vegetable Seed
Market (2001-2002)

24. Requirements of Heterosis Breeding
 Standard heterosis
 Pollination control mechanisms
 Self incompatibility
 Male sterility
 Extent of out crossing
 Economic viability

25. STEPS OF HYBRID SEEDS PRODUCTION
Production of inbred lines
In Self-Pollinated : Pure line
In Cross-Pollinated : Inbreeding or Selfing
Testing of Uniformity of Parents
Testing of combining ability
GCA for additive Gene Actions
SCA for dominant Gene Action
Predictive Information from SCA BY
(Single Cross, Double Cross, Three way Cross, Top Cross Poly Cross
and Diallel)
Improvement of inbred lines / varieties
For Disease and quality Trait
Back Cross and Convergent
Production of hybrid seed
Types of Hybrids and their Seed Production
Hybridization

26. Types of Hybrids
 Single Cross AxB
 Three-Way Cross (AxB) x C
 Double Cross (AxB) x (CxD)
 Modified Single Cross (AxA’) x B
 Modified Three- Way Cross (AxB)
x (CxC’)
 Top Cross A x OPV
 Double Top Cross (AxB) x OPV

27. METHODS OF HYBRID SEED
PRODUCTION

28. Mechanisms/Methods for Developing
Commercial Hybrids in Vegetables
Mechanism Commercially exploited in
Hand emasculation + HP Tomato, eggplant, sweet pepper, okra,
hot pepper
Pinching of staminate flowers + HP Cucurbits (bitter gourd, bottle gourd
etc.)
Male sterility + HP Tomato, hot pepper, sweet pepper
Male sterility + NP Onion, cabbage, cauliflower, carrot,
radish, muskmelon, hot pepper
Self-incompatibility + NP Most of the cole vegetables like
broccoli, cabbage, etc.
Gynoecism + NP Cucumber, muskmelon
Pinching of staminate flowers + NP Cucurbits including bitter gourd,
summer squash etc.
PGR and pinching of staminate flower +
NP
Summer squash, winter squash etc.
HP = hand pollination, NP = natural pollination Kumar and Singh (2004)

29. Commercially Unexploited Mechanisms for the Development of
Hybrids in Vegetables
Mechanism Vegetable Remarks Reference
Nuclear male
sterility
Tomato Monogenic mutant was utilized to develop cost effective
experimental crosses.
Sawhney, 1997; Kumar
et al.,2001
Synthetic
seeds
Celery and
lettuce
Celery and lettuce hybrids were successfully multiplied (in vitro)
through embryoids
Sakamoto et al.,1991
Nuclear male
sterility
Watermelon The utilization of monogenic recessive mutant was proposed. Zhang et al., 1994
Nuclear male
sterility
Cabbage Proposed feasible use of a dominant male mutant to produce
hybrid seeds; multiplication of male sterile line has been
proposed with the aid of tissue culture.
Fang et al., 1997
Functional
male sterility
Eggplant A monogenic recessive mutant was identified and proposed for
commercial utilization
Pathak and Jaworski,
1989
Nuclear male
sterility
Bottle gourd Male sterile were identified and characterized and utilized to
develop experimental crosses
Dutta,1983
Gynoecism Bitter gourd Gynoecious plants were identified and proposed for utilization
after genetic characterization
Ram et al., 2002
Chemical
hybridizing
agents
Several
vegetables
Experimental crosses were developed and proposed for
commercial utilization
McRae,1985
Transgenic
male sterility
Several
vegetables
Few of them are at the edge of commercial utilization. Williams et al., 1997
Kumar and Singh (2004)

30. Male sterility
 Male sterility in plants
implies their inability to
produce or release
functional pollen and is
result of failure of formation
or development of
functional stamens,
microspore or gametes.

31. On phenotypic basis
1. Sporogenous male sterility (eg dry/sticky pollen)
2. Structural male sterility (eg exerted stigma, stamenless filower in L.
hirsutum)
3. Functional male sterility (failiure of anther dehiscence; eg tomato &
brinjal)
On non genetic basis
1. Chemical male sterility
2. Physiological male sterility
3. Ecological male sterility
On genetic basis (spontaneous or induced)
1. Genetic male sterility
i) Temperature sensitive genic male sterilty
ii) Photoperiod sensitive genic male sterilty
iii) Transgenic male sterilty
2. Cytoplasmic male sterility
3. Cytoplasmic genetic male sterility
Classification of Male sterility

34. Linkage of ms gene with the
marker gene in vegetables
Vegetable Marker gene References
Broccoli Bright green
hypocotyle
Sampson, 1966b
Tomato • Potato leaf shape &
green stem colour
•Parthenocarpic fruit
•Enzyme markers
• Purple coloured
hypocotyle
•Kaul,1988
•Soressi &
Salamini,1975
•Tanksley et
al.,1984
•Pantnagar
Watermelon Delayed green
seedling
Zhang et al., 1996

38. Hybrid Seed Production through CGMS

39. Role of PGRs in Male Sterility
Crops PGRs in male sterile
line
References
Rice (GMS) Reduced level of GA Nakajima et al., 1991
Soybean (GMS) Reduced level of IAA and
ABA
Skorupska et al., 1994
Tomato (GMS) Reduced level of GA & GA
like substances
Increased level of IAA
Reduced level of cytokinin &
increased level of ABA
Sawhney, 1974
Singh et al., 1992
Sawhney, 1997
Santokh & Sawhney, 1998
Rapeseed (GMS) Reduced level of cytokinins
Increased level of IAA &
ABA
Sukla & Sawhney, 1992
Sukla & Sawhney, 1994
Rapeseed (CMS) Reduced level of cytokinins
& IAA
Increased level of ABA
Singh & Sawhney, 1992
Sawhney, 1997

40. Chemically Induced Male Sterility
Male sterility induced by chemicals ( called male gametocides or
chemical hybridizing agents)
Chemical Crop
Etheral Rice, Sugarbeet, Wheat
FW 450 Cotton, Groundnut, Sugarbeet, Tomato
GA3 Lettuce, Maize, Onion, Rice, Sunflower
MH Cucurbits, Onion, Tomato, Wheat
Sodium methyl arsenate Rice
Zinc methyl arsenate Rice

41. Male Sterility in Selected Vegetables
GMS :
• More than 55 male sterile (ms) alleles causing
sporogenous, structural & functional male sterility (Kaul,
1988)
• ms-1035 is linked with a recessive marker gene (a)
responsible for absence of anthocyanin (Georgiev,1991)
• Stamenless mutant sl-1 & sl-2
- flowers without stamen at high temperature
(280C/230C) while at low temperature (18 0C/15 0C)
produce flower with abnormal stamen ( Sawhney,1997)
• ms-15 & ms-33 mutants (at low temp;<300C associated
wit fertility restoration) (Sawhney,1997)
Tomato
Contd….

42. Male Sterility in Selected
Vegetables
CMS & CGMS :
 Through protoplast fusion of Lycopersicon
esculentum with Solanum acuale & S.
tuberosum, cytoplasmic male sterile cybrid
plant with different flower morphology have
been isolated (Melchers et al., 1992)
 Male sterile cytoplasm from Lycopersicon
esculentum has been transferred into L.
pennelli & then CMS pennelli has been
successfully crossed with esculentum
(Petrova et al., 1999)
Tomato

43. Male Sterility in Selected Vegetables
GMS :
- First documented by Martin & Grawford (1951)
- First male sterile plant was isolated from an Indian
accession PI -164835 (Petersan, 1958)
Dr Pochard introduced ms–509 line (Bell pepper) in PAU
Ludhiana & was introgressed in 3 chilli genotypes viz,
MS–12, MS-13 & MS-41 (Singh & Kaur, 1986)
Shifriss & Pilowsky (1993) developed a digenic system
ms-1ms-1, ms-2ms-2 X Ms-1ms-1, Ms-2ms-2, which
yielded 3 male sterile vs 1 fertile progenies due to
complementary gene action.
MS-12 : first commercial male sterile based chilli hybrid
by the Indian public sector (Kalloo et al., 1998)
Pepper
Contd….

44. Male Sterility in Selected
Vegetables
CMS & CGMS :
 In Peterson cytoplasm, pollen fertility restored
under 230C & 170C day & night temperature
(Shifriss, 1997)
 Sterile cytoplasm also obtained by back cross
progenies of Capsicum frutescens X C. annum
(Yoo, 1990)
 Not utilized commercially because of unstability
of Peterson type sterile cytoplasm
Pepper

45. Male Sterile and Fertile Flower in
Capsicum

46. Male Sterility in Selected
Vegetables
GMS : Cole vegetables
MS
line
Cole crops
ms-1 Sprouting Broccoli, Cabbage
ms-2 Cauliflower, Brussels Sprout, White
Cabbage
ms-4 Brussels Sprout
ms-C Cauliflower
 Chromosomal monogenic dominant MS – in Chinese Cabbage
Contd….

47. Male Sterility in Selected Vegetables
CMS & CGMS :
- First CMS system was developed by Pearson (1972)
through interspesific hybridization between Brassica
nigra (wild mustard) & B. oleracea var italica (broccoli)
& establish 2 CMS system :
1. Petaloid anther male sterility
- Flowers less attractive to pollinating insect
- Pistils enlarged, malformed & lacking nectaries
2. Vestigial anther male sterility
- Flowers smaller, normal with functional nectaries but
having vestigial anther
Contd….
Cole vegetables

48.  Transfer of Orgura cytoplasm of Raphanus
to broccoli (McCollum, 1981); cauliflower
(Hoser, Kranse & Antosik, 1987); Brussel’s
sprout (Bannerot et al,1974) and in cabbage
(McCollum, 1988). But seedling of all these
CMS line developed chlorosis in seedling &
young leaves lead to delayed maturity.
 Transfer of sterile ‘Anand’ cytoplasm from
B. rapa (originally derived from wild spp B.
tounetortii) to B. olearcea through
protoplast fusion ( Cardi & Earle, 1997)

49. Male Sterility in Selected
Vegetables
GMS :
 Spontaneous GMS mutants arises frequently in
cultivated field of N- India (Kaul,1988); controlled by
single recessive gene.
CMS & CGMS : 3 types of CMS
1. Degenerative corolla
2. Shrivelled stamen
3. Abortive pollen
Radish

50. Male Sterility in Selected Vegetables
GMS :
 Due to shrivelled, brown & non exerted anther
CMS & CGMS : 3 types of CMS
1. Petaloid type
- anther transformed into petal or petal like structure,
unable to produce functional pollen
2. Brown anther type
- present in all orange type cultivars
- deformed, brown coloured anther without functional
pollen
3. Gum type
- derived from cross with D. carota var gumifera
- total reduction of anthers & petals
 In USA vast majority of hybrids are produced from one
cytoplasm i.e. Cornell cytoplasm
Carrot

51. Flower Phenotypes in Carrot
a) Normal (N-cytoplasm, restored CMS plants)
b) Brown anther CMS (Sa)
c) Petaloid CMS (Sp)
Morelock et al.,1996

52. Male Sterility in Selected Vegetables
 First report of MS within progenies of an
onion cultivar Italian Red (Jones &
Emeweller, 1936); Male sterility
controlled by male sterile cytoplasm &
recessive nuclear gene (Jones & Clarke,
1943)
 2 types of Cytoplasm
1. S - cytoplasm
- anther morphology is normal but at anthesis
these are green, small & indehiscent
2. T - cytoplasm
- anther morphology is disrupted.
Onion
Bennekam, 1979

53. Male Sterility in Selected
Vegetables
 First recessive male sterile gene was
reported by Bohn & Whitaker (1949)
 ms-2, ms-3, ms-4, ms-5 have been
identified (Lecouviour et al.,1990)
 First commercial hybrid in vegetable crops
by male sterility : Punjab Hybrid-1 (ms-1 X
Hara Madhu) (Sandhu & Lal, 1999)
Muskmelon

54. SELF INCOMPATABILITY
 Inability of a fertile hermaphrodite plants to
produce zygote after self pollination
( Lundquist,1964)
 S.I. first reported by Koelreuter in the middle of 18th
century.

55. CLASSIFICATION OF S.I.
( Lewis, 1954)
 Heteromorphic system
 Homomorphic system
Gametophytic control
Sporophytic control

56. Examples of GSI
CROP REFERENCES
Solanum spp. Whalen and Anderson (1981)
Lycopersicon
peruvianum
William & Webb (1987),Chung
et al (1993,1999), Rivers et al
(1993), Chawla et al (1997)
Solanum tuberosum Thompson et al (1995), Kirch
et al (1989), Ortiz et al (1994)
Solanaceae Franklin & Franklin ( 2003),
Stone, J. L.(2002)
Solanum carolinense Lu, Y.(2006)
Solanum chacoense Qin et al (2005), Xu et al
(1990)
Physalis ixocarpa Pena & Marquez (1990)

57. Examples of SSI
CROP REFERENCES
Cabbage Nasrallah, M.E (1979), Horal & Kucera
(1983), Zur et al (2003), Fang et al (2004)
Cauliflower Nieuwhof, M(1974), Ram, H.H.(1975), Hoser,
K.J. (1981), Sharma et al (2003)
Sprouting broccoli Kalia & Sharma(2004),
Brussels sprout Smith & Mee (1984)
Chinese cabbage Tao et al ( 1982), Pilvek, K (1985), Na et al
(1992), Wen et al (2005)
Turnip Jeong & Oh(1996), Prasad, C(2004)
Radish Kalia, P (2004), Seo et al (2004)
Sweet potato Tomita et al (2004)

58. TECHNIQUES TO OVERCOME SELF
INCOMPATIBILITY IN CAULIFLOWER
TECHNIQUES USED REFERENCES
Bud pollination Rauala (1972), Singh et al
(1988), Gangopadhyay et al
(1995), Damke et al (2004)
Cross pollination followed by selfing Ockendon & Currah (1978)
Saline solution Carafa & Carrata (1997)
Okadaic acid Scutt et al ( 1993)
High frequency alternating electric current Roggen (1982)
3% NaCl for 0.5-1 hr Kucera (1990)
CO2 (4-6%) at 100% RH Polloix et al (1985)

59. TECHNIQUES TO OVERCOME SELF INCOMPATIBILITY
IN CABBAGE
TECHNIQUES USED REFERENCES
Bud pollination Sveatchevici & Nastase
(1972)
Gamma rays Hosoda et al (1973)
Thermally aided
pollination
Roggen & VanDijk (1976)
Pollen laser treatment Ilieva & Alipievo (1996)
Lower temp.(120 C), high
RH (90%)
Zur et al (2003)

60. TECHNIQUES TO OVERCOME SELF
INCOMPATIBILITY IN BRUSSELS SPROUT
TECHNIQUES USED REFERENCES
Bud pollination Roggen & VanDijk(1972)
GA3 Sastri (1984)
Cross pollination followed by
selfing
Holland & Mcneilly (1999)
High temperature Ockendon (1973)
Alternating temperature Visser (1977)
Thermally aided pollination Roggen & VanDijk (1976)

61. SI and Production of Hybrid
Seed by Single Cross
Line A : S1S1 X Line B: S2S2
s1 s 2
F1 Single cross hybrid S1S2 (Self-incompatible)

62. Scheme for The Production of
Hybrid
Seed by Three Way Cross
Female Line Male Line
S1S1 X S 2S2
S1S2 X S3S3
Female Line Male Line
S1S3 , S2S3
(Self and sib incompatible)
If S3 is dominant over S1S2

63. Scheme for The Production of
Hybrid Seed by Triple Cross
S1S1 X S 2S2 S4S4 X S5S5
S1S2 X S3S3 S4S5 X S6S6
S1S3 , S2S3 X S4S6 , S5S6
Hybrid seed produced by triple Cross
(S1S4, S1S6, S3S4, S3S6, S2S, S2S6, S1S5, S1S6, S3S5, S2S6, S2S5, S2S6 )

64. Manual Emasculation &
Pollination

66. Hand Pollination: Without
Emasculation
Applicable for monoecious cucurbits (Cucumber,
Squash, Pumpkin, Bitter gourd)
Seed plant Pollen plant
Female flower Male flower
Apply pollens on stigma of female flower
(after anthesis)
Bagging (before anthesis)
Bagging – F1 seed collected
Planting ratio:
Cucumber 5:1
Watermelon 6:1

67. Gynoecious × Monecious most widely used.
Steps:
Planting ratio (3 gynoecious female line: 1 pollinator line).
Natural pollination by bees.
Any other variety except parents should not be there.
Blending – to improve pollination in gynoecious hybrid seeds (10%
monoecious types.
Sumter cultivar – most common blender.
If parthenocarpic gynoecious hybrid – no blending.
Commercial gynoecious hybrids
 In cucumber
 Pusa Sanyog,
 DCH-1, 2 (T.A. More and V.S. Sheshadri in early ninties),
 Phule Prachi (Gyc-2) and Phule Champa (Gyc-4) (More, 2002)
 In muskmelon
 MH-10 (Dhatt et al.,2005)
Use of Gynoecious Lines and
Insect Pollination

68. Sex Manipulation for Hybrid Seed Production
1950 – Laiback & Kribbeu – NAA & IAA increase proportion of pistilate
flowers
1979 – Shannon & Robinson – 600 ppm ethylene results in complete
suppression of male flowers in summer squash
1980 – Rudich – endogenous ethylene controls sex expression in
muskmelon, cucumber & squash.
1981 – Hume and Lovell – ethepone reduced 90% labour requirement in
hybrid seed production
1985 – Singh & Chaudhary – 200-300 ppm ethrel at 2 and 4 true leaf stage,
suppress the staminate flowers in bottle gourd, pumpkin and squash.
2005 – Sirohi and Sarkar – etheral (400-500ppm) - complete suppression of
male flowers in squash.
2005 – Papadopoulou and Grumet – brassinosteriod (BR) @10ppm sufficient
to increase femaleness in cucumber.
Steps:
Planting ratio : 5:1 in Cucurbita pepo
2-true leaf stage is most responsive for application of chemicals
Natural pollination/hand pollination.

69. Foliar Spray of PGRS to Induce Increased Proportion
of Pistillate Flowers
PGR Conc (mg/l) Cucurbits
Cycocel (CCC) 250-500 Most cucurbits, effective in
cucumber
Ethephon (CEPA) 150-200 Most cucurbits
Gibberellic Acid (GA) 150-200 Watermelon
Indole acetic acid
(IAA)
10 Snake gourd & bitter gourd
NAA 20-200 Cucumber, melons & gourds
Maleic hydrazide (MH) 25-100
50-150
Cucumber, muskmelon, bottle
gourd, ridge gourd
Rai et al., 2005

70. Use of Monoecious in Spinach
 Single cross
 Three way cross
Highly female monoecious(5-6) : Highly male monoecious(1-2)
Single cross
(Echo and Prima)
Rouging of male
plants (1-2%)
(Sparse foliation
and early
bolting)
Highly female monoecious F1(5-6) : Highly male monoecious(1-2)
Three way cross

71. Biotechnological tools useful in Hybrid
seed production
Tissue culture
 Clonal Multiplication via
in vitro fertilisation
 Haploid culture
 Protoplast fusion
Transgenic
approaches
 for male sterility
 for developing resistant line
 terminator seed technology
Molecular Marker

72. Application of clonal
multiplication via in vitro
fertilization in vegetable crops
Mass multiplication of S.I. Line of cabbage and
cauliflower

73. Application of haploid culture in
Vegetable crops
CROP FINDINGS REFERENCE
Tomato Haploidy has been
successfully used for
developing male sterile
pure line
Zamit et
al.1980
Schereva et.al.
1990
42% MS plant+34%
normal plant obtained by
culturing cv.Roma & MS
line with ms 1035
Oankh et
al.1986

74. CROP FINDINGS REFERENCE
Chilli and
capsicum
A new variety Haihua-
3 developed in China
Li & Jiang
1990
4 homozygous
resistant line for PVY
& PVMV
Selassie et al.
1986

75. CROP FINDINGS REFERENCE
Brinjal
Haploid plant
produced by anther
culture in egg plant
Damusole &
Vaulx,1982
Cole crops Efficient application
of haploid induction
in cabbage and
Brussels sprout
Rudolf et al.,
1999

76. Production of male hybrid
in asparagus
XY (male asparagus)
anther culture
X Y
(haploid plant)
chromosome doubling
XX X YY
normal female fertile male
XY (male hybrid)

77. .
Study Reference
In carrot MS lines were produce by fusion
protoplast of male fertile and CMS lines.
Jourdan et al. (1985)
Brassica + Raphnus cybrid that contain nucleus of
Brassica nappus chloroplast of B. campestris and
mitochondria of R. sativus that confer CMS.
Pelletier et al. (1988)
Effective transfer of CMS from radish to rape has
been achieved.
Paulmann and
Robbelen (1988)
Cold tolerance CMS cabbage is produce by fusion
of cabbage protoplast with cold tolerant ogura
CMS broccoli line.
Sigareva and Earle
(1997)
CMS chicory have been obtain by fusion between
chicory and CMS sunflower protoplast.
Ramband et al. (1997)
In carrot transfer of CMS from D. carota sub sp.
gemmifera, maritimus has been tried.
Bach et al.(1997)
Transfer of CMS in many crop plants
Significance of protoplast fusion in
hybrid seed production

78. Use of molecular marker
Identification of genotype:
 Advantageous to select parent for F1hybrid
production.
 Assessment of relationship between parent
and hybrid.

79. Identification of genotype
Carrot Screening of inbred lines and 3
F1 hybrids using 33 decamer
primer
Grzebems et al.
(1997)
Pea Identification of F1 hybrid by
RFLP marker
Polans et al. (1990)
Broccoli Purity test of F1hybrid by RFLP
analysis
Sakamoto et al.
(2000)
Ash gourd Molecular diversity and its
relation with hybrid
performance and heterosis
Behera and
Matapatra (2004)
Water melon Genetic relationship between
parents and F1hybrid
Che et al. (2002)

80. Strategies for producing
transgenic male sterility
A. Barnase-Barstar system.
B. Hormone inducible male sterility
based on Bcp1.
C. Antisense gene approach.

81. Use in hybrid seed production
 Most of the transgenics MS system are
developed by MNCs and few of them are near
the edges of utilization of hybrid seed
production programme. (Williams et al. 1997)
 Achievements : B. napus, tobacco, petunia.
 Target crop: tomato, lettuce, cauliflower, corn.
 In India first hybrid MH-11 developed by using
transgenic MS line in B. napus, at Delhi
university south campus.

82. List of some public and private sector bred hybrids
identified and released for cultivation
Crop/Hybrid Developing Centre
Brinjal
Pusa Hybrid-5 IARI
NDBH-6 NDUAT
ARBH-201 Ankur Seeds
Pusa Hybrid-6 IARI
NDBH-1 NDUAT
MHB-10 MAHYCO
Pusa Hybrid-9 IARI
PBH-1` GBPUAT
Arka Navneet IIHR
Azad Hybrid CSAUAT
ABH-1 GAU
ABH-2 GAU
MB-39 MAHYCO

83. Tomato
ARTH-3 Ankur Seeds
ARTH-4 Ankur Seeds
ARTH-6 Ankur Seeds
MTH-6 MAHYCO
Pusa Hybrid-2 IARI
NA-501 Nath Seeds
NA-601 Nath Seeds
DTH-4 IARI
Avinash-2 Novartis
HOE-303 Novartis
FMH-1 IIHR
KT-4 IARI
Arka Vardan IIHR
Sun-496 Sungrwo
Chilli
CH-1 PAU
HOE-888 Sandoz
ARCH-236 Ankur Seeds
Bell Pepper
KT-1(Pusa Deepali) IARI

84. Cabbage
Pusa Synthetic IARI
Sri Ganesh Gol MAHYCO
Nath-401 Nath Seeds
BSS-32 Bejo Sheetal
Quists Novartis
Cauliflower
Pusa Hybrid-1 IARI
Muskmelon
Pusa Rasraj IARI
Punjab Hybrid-1 PAU
M-3 Hybrid IARI
Watermelon
Arka Jyoti IIHR
MHW-6 MAHYCO
Bottle gourd
Pusa Meghdoot IARI
Pusa Manjari IARI
PBOG-1 GBPUAT
PBOG-2 GBPUAT

85. Cucumber
Pusa Sanyog IARI
Okra
DVR-1 IIVR
DVR-2 IIVR
Carrot
Hybrid-1 IARI
Onion
Arka Pitamber IIHR
Arka Kirtiman IIHR
Pumpkin
Pusa Hybrid-1 IARI
Summer Squash
Pusa Alankar IARI

86. Major constraints
• High cost of F1 hybrid seeds.
• Lack of awareness among the growers
about hybrid crop production techniques.
• Unorganised marketing system for
vegetables.
• Lack of postharvest management
techniques.
• Nonavailability of quality seeds.
• Nonavailability of other inputs at proper
time.
• Nonavailability of biotic stress resistant
hybrids.

87. Research priorities
 To develop multiple resistant hybrid
varieties against major biotic
stresses.
 To develop off-season vegetable
hybrid varieties.
 To utilize available genetic
mechanisms more effectively for
hybrid seed production.

88. Research priorities for developing multiple
resistant hybrids against biotic stresses
Crop Target biotic stresses
Tomato TLCV, early blight, bacterial wilt, RKN
Brinjal Phomopsis, bacterial wilt, fruit and shoot borer
Chilli Leaf curl, thrips, mites, anthracnose
Capsicum Phytophthora, thrips, mites
Okra YVMV, fruit borer
Onion Stemphyllium, purple blotch, thrips
Cucumber DM, mosaic
Muskmelon PM, DM, anthracnose, Fusarium
Watermelon PM, DM, anthracnose
Cabbage Black rot, diamond black moth
Cauliflower Black rot, diamond black moth

89. Research priorities for hybrid seed
production system and specific trait
Crop F1 seed production system Heterosis breeding aim
Tomato GMS, GCMS Tolerant to high temperature,
high TSS, high lycopene
Chilli GMS, CMS High oleoresin
Capsicum Use of protected infrastructure in
plains
Adapted to the plains of North
India
Cauliflower Strong SI, CMS Heat tolerance
Cabbage SI, CMS Tolerant to high temperature
Onion Short day CMS lines Photoperiod insensitive
Carrot CMS High carotene %
Watermelon MS lines High TSS, seedless
Muskmelon Ms lines High TSS
cucumber Gynoecious lines Pickling type

90. Other priorities
 To develop crop and location specific production
techniques for hybrid variety.
 Parental lines can be made available to private
sectors (companies/seed producers).
 To streamline the development of hybrids and F1
seed production, development of infrastructures
like greenhouse, net house and poly house with
drip irrigation system.
 Development of sound postharvest management
techniques.
 Promotion of cooperative society to ensure
adequate supply of quality F1 seeds and other
inputs at proper time.
 Training programmes.

92. Thank you….