breeding for disease resistence in cucurbites

1. 1
welcome

2. 2
Seminar-I
PRAKASH, M.
UHS10PGM40
Dept. of GPB
KITTUR RANI CHANNAMMA COLLEGE OF HORTICULTURE, ARABHAVI 591310
Breeding for disease resistance in
cucurbits
on

3. 3
Introduction
Sources of resistance
Screening for resistance
Mechanism of resistance
Genetics of resistance
Breeding for resistance
Achievements
Conclusion

4. 4
 The cucurbitaceous vegetables comprise of cucumber, gourds,
melons, squashes and pumpkins
 Most of these vegetables are subjected to infestation by many
diseases leading to heavy loss
 Cucurbits are favorable host to many diseases because of their
succulence nature
 Among the various diseases the most devastating are downy
mildew, powdery mildew and mosaics

5. Disease development
5
Agrios, 1998

6. 6
 Immune reaction
No attack of pathogen on host
 Resistance
Symptom and reproduction lower then those in susceptible
 Tolerance
With the same level of infection , a lower reduction in the yield
Susceptible reaction
Symptoms and reproduction unchecked by host genotype
Disease resistance
Agrios, 1998

7. 7
 Active resistance
The pathogen, due to the biosynthesis of some chemical
substances
 Passive resistance
The resistance is due to the qualities innate in the host prior to
the attack of the pathogen
 Field resistance
Host capability to restrict pathogen proliferation under field
conditions
Types of disease resistance
Agrios, 1998

8.  Disease escape
A specific environmental factor
 Hypersensitivity
The prompt death of the tissue round the point of pathogen entry,
prevents further spread of infection .
 Durable resistance
The resistance which exhibits uniformity and stability over longer period
 Antibiosis
Resistance conferred by the presence of certain toxic substances
8
Contd….

9. 9
Classification of resistance
1. Genetic nature
a. Monogenic
b. Oligogenic
c. Polygenic
d. Cytoplasmic
2. Based on growth stage of host
a. Seedling resistance – juvenile resistance
b. Adult resistance – Mature plant resistance
3. Based on epidemiological term ( Vander Plank)
a. Vertical resistance
b. Horizontal resistance

10. 10
Mechanism of disease resistance
1. Morphological / Biophysical feature
Small sunken and hairy stomata with Lesser opening duration of
flower have been found associated with disease resistance in
different crop plants.
2. Hypersensitivity
This delays an epidemic and contributes to a defense
mechanism against specific race of a pathogen.
3.Biochemical features
Toxic compounds in cucurbits cucurbitacins, saponins,
glycosides alkaloids, amino acids and Xanthophylls.

11. 11
 A known variety
Sources of resistance & good agronomic characters
 Germplasm collection
Potential sources of resistance in cultivated crops.
 Related species
Resistance to a disease may not be concerned crop species
 Mutants
Artificial mutants may used in hybridization
 Somaclonal variants
 Unrelated organism
Sources of disease resistance

12. 12
 Disease resistance varieties
Chemicals: Fungicides and bactericides
 In some cases resistance breeding is the only feasible means
for disease control
 Disease resistant varieties are usually not affected by the
environmental condition
 Disease resistant varieties can be effectively combined with
other measures of disease control
Advantages of breeding for disease resistance

13. 13
Cultivated species with their common and
scientific name of the Cucurbits System
Common name Scientific name
Pumpkin Cucurbita moschata
Summer squash Cucurbita pepo
Winter squash Cucurbita maxima
Water melon Citrulus lanatus
Musk melon Cucumis melo
Cucumber Cucumis sativus
Chow-chow Sechium edule
Ridge gourd Luffa acutangula
Sponge gourd Luffa cylindrica

14. Cont...
Common name Scientific name
Bitter gourd Momordica charantia
Bottle gourd Lagenararia siceraria
Snake gourd Trichosanthus angunia
Snap melon Cucumis melo var. momardica
Gherkin Cucumis anguria var.anguria
Little gourd Coccinia indica
Ash gourd Benincasa hispida
Pointed gourd / parwal Tricosanthus dioica
Ivy gourd Coccinia cordifolia
Long melon Cucumis melo var. utilissimus
Agrios, 1998

15. 15
Important diseases of Cucurbits
Common name Causal organisms
Anthracnose Colletotrichum orbiculare
Cercospora leaf spot Cercospora citrullina
Damping off Phytopthora spp.
Downy mildew Pseudoperonospora cubensis
Powdery mildew Sphaerotheca fuliginea
Fusarium wilt Fusarium oxysporum f. sp. cucumerinum
Fusarium oxysporum f.sp. niveum
Fungal diseases
Agrios, G.N. 1998

16. 16
Bacterial diseases
Common name Causal organisms
Angular leaf spot
Pseudomonas syringae
pv. lachrymans
Bacterial leaf spot
Xanthomonas campestris
pv. cucurbitae
Bacterial wilt Erwinia tracheiphila
Agrios, 1998

17. 17
Common name Causal organisms
Cucumber green mottle Cucumber green mottle mosaic
virus (CGMMV)
Cucumber mosaic Cucumber mosaic virus (CMV)
Cucumber vein yellowing Cucumber vein yellowing virus
(CVYV)
Melon necrotic spot Melon necrotic spot virus
(MNSV)
Squash leaf curl Squash leaf curl virus (SqLCV)
Watermelon mosaic Watermelon mosaic virus
(WMV)
Zucchini yellows Zucchini yellows mosaic virus
(ZYMV)
Virus diseases
Agrios, G.N. 1998

18. Table 1: Percent yield loss by different diseases in cucurbits
Crops Disease Yield loss(%) Reference
Muskmelon, watermelon,
Cucumber
Powdery
mildew
75 Tafradzhii, 1969
Muskmelon, watermelon,
cucumber and squashes
Downy
mildew
79.06
Mahrishri and
Siradhara,1988
Muskmelon, watermelon,
cucumber and gourds
Anthracnose 89.5
Mahrishri and
Siradhara, 1988
Muskmelon, watermelon,
cucumber
Fusarium wilt 80 Mune et al.,2001
Muskmelon, watermelon,
cucumber and squashes
Cucumber
mosaic
96
Kazada et al.,
1999
Muskmelon WMV 70 Mayee et al., 1976
Watermelon WBNV 71 Pandey, 2001
Indian melon CABYV 40
Catherine et al.,
1997

19. Table 2: Sources of resistance for different diseases in cucurbits
Crop Diseases Sources
Cucumber
Anthracnose
PI 175111, PI 175120, PI 179676, PI 182445,
Wise 2757
Downy mildew B -184, B159, Wise 2757 (USA), SC2B-4,
Powdery mildew
PI 200815, PI 200818, C. hardwikkii, Wise 2757
(USA)
CMV
Wise SMR-12, SMR-15, SMR-18, Wise 2757
(USA)
Bottle gourd
CMV, SqMV, WMV PI 271353
Fusarium wilt Taiwan variety Renshi
Pumpkin
PM and Viruses Cucurbita lundelliana, Cucurbita martenezii
ZYMV, WMV
Cucurbita ecuadorensis, C. faetidistima, C.
martenezii
Summer
squash
Watermelon mosaic
virus
Cucurbita ecuadorensis, Cucurbita foetidissima
Winter squash Powdery mildew, WMV Cucurbita martinezii (Bhagirath et al., 1991)

20. Crop Diseases Sources
Watermelon
Fusarium Wilt
EC 333659, EC 333669, Summit, Conqueror,
Charleston Gray, Dixilee, Crimson Sweet (Norton
et al., 1986)
Fusarium and
anthracnose
EC 382753, EC 383809, EC 402549 , Fair,
Charleston Gray, Congo, PI 189225 (Sitterly, 1972)
ZYMV PI 381825.PI-381831 (Shu and Amnon , 2007)
Muskmelon
Watermelon mosaic
virus
EC 350603, PI 414723, B66-5, MR-12
WMV, Powdery mildew EC 350604, MR-12 (Pan et al.,1994)
Fusarium wilt
Cucumis figarei, Cucumis zeyheri (Pan et
al.,1994)
Downey mildew
EC 399917, MR-1, PI 414723, MR-12 (Dhiman et
al., 1994)
Powdery mildew
EC 399934, PM R 45, PMR 5, PMR 6, Iroguis
(Pan and More, 1996)
Contd…

21. 21
Screening for resistance

22. 22
SCREENING TECHNIQUES
Soil born diseases: Like root rots, collar rots, wilts, etc. the screening is
done in disease sick plots
Air born diseases: Like rusts, smuts, mildews, blights, leaf spots, etc., The
screening is done either by dusting the spores or by
spraying spore
Seed born diseases: Seed borne disease like smuts and bunts, either dry
spores are dusted on the seeds
Insect transmitted diseases: The insect from susceptible varieties are
collected and released on healthy plants

23. 23
Downey mildew in cucurbits

24. Table 3: Varietal screening of ridge gourd genotypes against downy mildew at
different locations Thammaiah et al., 1999, UAS, Dharwad
24
Genotype
Bijapur Arabhavi
Leaves
affected (%)
Leaf area
affected (%)
Leaves
affected (%)
Leaf area
affected (%)
Jaipur Long 60.55 26.66 86.70 37.0
Japanese Long 51.11 28.96 61.11 9.0
Raichur Local-2 39.99 22.20 31.00 3.0
Deodurage Local 42.77 26.93 68.90 3.4
Govnal Local 47.22 29.33 31.11 4.2
Poona Local 51.66 26.83 58.50 12.2
Ittanahalli Local-1 44.44 26.20 80.00 24.0
Ittanahalli Local-2 64.99 24.40 73.30 21.5
Jumnal Local 60.00 25.10 69.10 21.0
Kotiyal 64.44 32.90 48.80 12.0
Pusa Nasdar 67.33 34.83 100 52.0
C. D. @ 5% 12.46 NS 12.37 10.23

25. 25
Powdery mildew in cucurbits

26. 26
Table 4: Reactions of various germplasms of Cucurbita moschata to powdery mildew
(Sphaeratheca fulginea) in nature
Kabitarani and Bhahgirath, 1991, Imphal
Germplasm Source Disease Index
P1 Jirabam (Manipur) 2.33
P2 Yaingangplokpi (Manipur) 2.78
P3 Kohima (Nagaland) 2.92
P4 Mao (Manipur) 2.8
P5 Imphal (Manipur) 2.83
P6 Chakpikarong (Manipur) 3.03
P8 Ukhrul (Manipur) 2.94
P9 Shillong (Meghalaya) 2.83
P11 Hojai (Assam) 2.97
P12 Silchar (Assam) 2.67
P13 Izwal (Mizoram) 2.22
P14 Izwal (Mizoram) 1.02
C.D.@ 5%=1.38

27. Anthracnose in water melon

28. 28
Table 5: Intensity of anthracnose (Colletotrichum lagenarium) diseases in
bottle gourd genotypes Mohan, 2009, Dharwad
Gen. Genotypes
Diseases score
(0-4)
Disease reaction
Cross-I
P1 KRCCH (KAG-1) 3 MS
P2 Kabbur (KAG-2) 3 MS
F1 KRCCH X Kabbur 4 S
F2 F1 self 4 S
BC1 F1 X KRCCH 3 Ms
BC2 F1 X Kabbur 3 MS
Cross-II
P1 CO-2 (KAG-3) 2 MR
P2 Bh-25 (KAG-4) 3 MS
F1 CO-2 x Bh-25 2 MR
F2 F1 self 4 S
BC1 F1 x CO-2 3 MS
BC2 F1 x Bh-25 3 MS

29. 29
Gent. Genotypes
Diseases score
(0-4)
Disease reaction
Cross-III
P1 ARS (KAG-5) 3 MS
P2 Shakti (KAG-6) 2 MR
F1 ARS x Shakti 3 Ms
F2 ARS X Shakti 3 Ms
BC1 F1 X ARS 2 MR
BC2 F1 X Shakti 3 MS
Contd…
Scoring( 0-4): 0 =I, 1= R, 2=MR, 3=MS, 4=S

30. 30
Fusarium wilt in cucurbits

31. 31
Table 6: Reaction of selected muskmelon genotypes to Fusarium wilt
under artificial inoculation conditions
Pan et al., 1994, New Delhi
Genotypes
Fusarium wilt plant (survival %)
Expt. 1 Expt 2 Expt 3 Mean
Cucumis figarei 100 100 100 100
C. zeyheri - 66.66 87.50 77.08
C. myriocarpus 100 - 50 75.00
5-4 (FM-1x Pusa Madhuras) 58.33 66.6 - 62.49
Phoot 5.55 53.80 41.66 33.65
Iraquois 50.00 33.33 0.00 27.77
Kakri 8.33 13.30 - 10.81
NC 62923 0.00 15.30 - 7.65
Pusa Madhuras 0.00 7.10 12.50 6.53

32. 32
Green mottle in cucumber

33. PURE ISOLATE
COMMON INOCULATION OF CUCUMBER GREEN MOTTLE MOSAIC VIRUS (CGMMV)
C. figarei C.ficifolius Phoot Kachri FM-1 M-3 PM
Symptom less Susctible
M3 M3 M3 M3 M3 M3 M3
Immune Resistance Susceptible
Fig 1: Diagrammatic representation of back inoculation for CGMMV in melons
Rajamony et al., 1999, Kerala
SEPARATE SAP TRANSMISSION AND INOCULATION

34. 34
Table 7: Screening of ridge gourd genotypes for downy mildew incidence
Kantharaja, 2003, Arabhavi
Parents / Hybrids % Plants Infected
P1 : Sel 4-12 33.20
P2 : (RCR-1) 12.70
P3 : Pusa Nasdar 47.83
P4 : Arka Sumeet 28.60
P5 : 25/ 4-2 29.80
P1XP2 22.40
P1XP3 26.55
P1XP4 31.65
P1XP5 19.02
P2XP3 25.40
P2XP4 22.75
P2XP5 20.25
P3XP4 16.70
P3XP5 18.40
P4XP5 16.78
Latha (cc) 20.70

35. 35
CMV WMV
Zymv in Squashes Zymv in pumpkin

36. 36

37. 37
Table 8. Pathogen reaction of TSWV on different cultivars of watermelon
Pandey and Pandey, 2001,Varanasi
Sl.No Variety PDI Reaction
1 Arka Manik 51.6 S
2 RW-187-2 48.5 MS
3 MHW-11 40.8 MS
4 ORWM 51.42 S
5 MHW-4 34 MS
6 MHW-5 44.6 MS
7 RW-177-3 71.4 HS
8 EC-393243 0 R
9 EC-393240 20.0 MR
10 Durgapur Mitha 20.0 MR
11 Durgapur Selection 0 R
12 MHW-6 22.3 MR
13 Arka Jyoti 36.67 MS
14 RHRWH-2 0 R
15 Ashey Questo 24.0 MR
16 Sugar Baby 39.1 MS0
S – Susceptible, MS – Moderately Susceptible, HS – Highly Susceptible
R – Resistance, MR – Moderately Resistance

38. 38
Table 9: A repeated test with selected accessions confirmed the resistance potential
in Lagenaria siceraria to zucchini yellow mosaic virus
Ling and Levi, 2007, Charleston
PI No. Origin
Primary screening Repeated screening
No.
plants
Susceptible Resistance
No.
plants
Suscepti
ble
Resista
nce
181948 Syria 6 6 0 3 3 0
280632 S. Africa 1 1 0 1 0 1
368636 Yugoslavia 6 6 0 5 4 1
370474 Yugoslavia 9 9 0 5 4 1
379367 Yugoslavia 12 12 0 4 4 0
406857 Honduras 5 5 0 5 3 2
381825 India 12 0 12 5 0 5
381831 India 9 0 9 2 0 2
381834 India 13 0 13 5 0 5

39. 39

40. 40
Table 10: Reaction of ridge gourd varieties to downy mildew
Kagadi et al., 2001, Dapoli
Variety
Percent disease intensity at DAS Reaction
type30 60 90 120
Kerala- 2 0.00 0.00 2.00 6.25 R
Kerala-1 0.00 0.00 6.16 10.00 R
KRG-5 0.00 1.00 7.25 14.16 MR
CH-RG-1 0.00 0.05 8.90 15.25 MR
CH-RG-2 0.00 1.26 14.28 20.00 MR
Pusa Nasdar 0.00 1.25 16.06 28.00 S
DRG-1 0.00 3.28 12.25 30.42 S
IIHR-6 0.00 1.28 18.32 38.50 S
IIHR-7 0.00 3.25 24.25 40.28 S
CO-1 0.00 1.25 25.26 41.00 S
PRG-7 0.00 5.61 27.16 43.06 S
PRG-6 0.00 2.05 25.01 50.01 HS
DPL-RG-2 1.00 9.28 28.00 55.25 HS
S – Susceptible, HS – Highly Susceptible , R – Resistance, MR – Moderately Resistance,

41. 41
Table 11: Reaction of selected muskmelon genotypes to fusarium wilt, powdery
mildew, downy mildew and CGMMV Pan and More, 1995, New Delhi
Genotypes
Fursarium wilt
Plant
(% survival)
PDI(%)
Powdery
mildew
Downy
mildew
CGMMV
Cucumis figarei 100.0 100 3.3 0.00
C. zeyheri 77.1 97.2 NT 0.00
PMR-1 12.5 7.5 53.7 24.8
FM-1 13.9 NT 54 17.1
Iroquis 27.8 4.2 41.7 40.0
Phoot( C. melo var. momordica) 33.7 100 14.0 15.0
VRM-1-3A 12.0 NT 6.7 35.9
VRM-1-3B 22.7 NT 38.3 26.5
VRM-5-10A 3.7 NT 46.7 10.8
VRM-5-10B 9.5 NT 46.0 21.5
VRM-7-12A 10 NT 32.5 16.9
VRM-29-IC 25.0 NT 50.7 18.8
Pusa Madhuras (S-check) 6.5 85 65.3 71.9
CGMMV: cucumber molted mosic virus

42. 42
Table 12: Reaction of different varieties of muskmelon to downy mildew, powdery
mildew and viral complex diseases under field conditions during different
years Dhiman et al., 1995, Punjab
Percent Diseases Incidence (PDI) in different years
Diseases 1989 1990 1991 Mean (%)
Downy Mildew
MR-12 3.66 19.83 14.43 12.64
Hara Madhu 6.92 45.42 18.29 23.54
Punjab Sunehri 6.53 28.33 15.38 16.75
Punjab Hybrid 6.67 14.72 24.63 15.34
LSD @ 5% NS 20.27 NS
Powdery Mildew
MR-12 0.64 2 5.08 2.58
Hara Madhu 44.74 27.33 5.98 26.02
Punjab Sunehri 17.28 18 11.76 15.68
Punjab Hybrid 5.34 0.67 10.89 5.63
LSD @ 5% 15.34 15.28 NS

43. 43
Percent Diseases Incidence (PDI) in different years
Diseases 1989 1990 1991 Mean (%)
Viral Mosaic
MR-12 8.88 10.65 13.25 10.93
Hara Madhu 22 24.25 40 29.08
Punjab Sunehri 14.37 22 39 24.12
Punjab Hybrid 34.87 27.25 9.25 23.79
LSD @ 5% 8.34 6.23 10.01
Contd…

44. 44
Genetics of disease resistance

45. 45
Genetic resistance refers to those heritable features of a host plant
that suppress or retard development of a pathogen.
GENETIC RESISTANCE
Vertical resistance Horizontal resistance

46. 46
Vertical resistance Horizontal resistance
 It provides protection only for one
race of a pathogen
It is usually short lived or less durable
The resistance can easily breakdown
when new race of a pathogen formed
Protection against several races of a
pathogen
It usually long durable
The resistance cannot be easily
overcome by new race of a pathogen
due to polygenic control

47. 47
For each resistance gene (R gene) in the host, there is
corresponding avirulence genes (avr gene) in the pathogen
(Flor, 1956)
Exploitation of vertical resistance by different methods.
1.Varieties with individual major genes
2.Development of multilines
3.Gene pyramiding
4.Gene deployment
Gene for gene hypothesis

48. 48
Exploitation of vertical resistance
• Varieties with individual major gene
Major gene is transferred for the prevalent
• Development of multilines:
seed mixture of isolines, related lines or unrelated lines
• Gene pyramiding
Incorporation of two or more major genes in the host for
specific resistance to a pathogen
• Gene deployment
strategic use of major genes in development of resistance
cultivars for various geographical areas

49. 49
Gene
Symbol
Resistance to Gene action References
Watermelon
Ar-1 Anthracnose resistance to races 1 and
3
Layton,1937
Ar-2-1 Anthracnose resistance to race 2 Winstead et al.,
1959
db resistance to gummy stem blight Norton, 1979
Fo-1 Fusarium wilt resistance for race 1 Dominant
gene
Henderson et
al., 1970
pm powdery mildew Recessive Robinson et al.,
1975
zym-FL Resistance to zucchini yellow mosaic
virus
Provvidenti,
1991
Zym-2 Zucchini Yellow Mosaic potyvirus
resistance.
Danin et al.,
1997
Table 13: Genes for disease resistance

50. 50
Muskmelon
Fn Resistance to muskmelon yellow
stunt virus.
Pitrat et al.,
1982
Mnr1&Mnr
2
necrotic spot virus resistance 2complimen
try dominant
gene
Coudriet et al.,
1981
Wmv Watermelon mosaic virus-1
resistance.
Single
dominant
Brown
et al.,2003
Cucumber
cmv cucumber mosaic virus resistance 3 recessive
genes
Dogimont
et al., 2000
Wmr Watermelon Mosaic virus 2
(potyvirus)
Gilbert et al.,
1994
Contd…

51. 51
Muskmelon
resistant
genes
Differential
host
Sphaerotheca fuliginea races
1 2 3
0 Delicious 51 S S S
Topmark S S S
Vedrantais S S S
Pm-1 PMR- 45 R S S
PMR- 450 R S S
Pm-1, Pm-2 PMR- 6 R R S
Perlita R R S
Pm-3 PI 124111 R R R
Pm-4, Pm-5 PI 124112 R R R
Seminole R R R
Table 14: Reaction of the known genes in muskmelon for resistant to
powdery mildew caused by Sphaerotheca fuliginea
James et al., 1997, USA
R= Resistant, S= Susceptible

52. 52
Lines Sf1 Sf2 Ec
PMR-45 Pm-A
WMR-29 Pm-A Pm-B
PMR 5 Pm- D and Pm-C Pm-c
Pm-c and
Pm-E
PI 124112 Pm-c Pm-c
Pm-F and
Pm-G
Nantais Oblong Pm-H
Table 15: Hypothesis for the genetic control of resistance to powdery
mildew in five melon lines Epinat et al., 1993, France
Sf - Sphaerotheca fuliginea Ec - Erisyphe cichoracearum

53. 53
Table 16: Segregation for resistance to powdery mildew caused by
Sphaerotheca fuliginea in muskmelon
Floris and Alvarez , 1995, Spain
Parents / cross
Observed number Test
ratio
χ2
R I S Value Prob.
Piel de Sapo(PS) 0 0 10
Moscatel Grande 10 0 0
Negro 10 0 0
Amarillo 10 0 0
Negro X PS
F1 10 0 0
F2 25 0 7 3:1 0.16 0.68
BCs 16 0 15 1:1 0.33 0.71
BCr 20 0 0

54. 54
Parents / cross
Observed number Test
ratio
χ2
R I S Value Prob.
Moscatel Grande x PS
F1 10 0 0
F2 30 16 2 9:6:1 0.59 0.74
BCs 10 22 8 1:2:1 0.60 0.74
BCr 30 0 0
Amarillo X PS
F1 30 0 0
F2 30 0 9 3:1 0.10 0.75
BCs 16 0 20 1:1 0.44 0.50
BCr 28 0 2
R= Resistance, I= Intermediate, S= Susceptible
R =Less than10% affected tissue, or less then 1 connidium/cm2 × ml
I=Among10% to 30 of % affected tissue, or 1 to 4connidium/cm2 × ml
S=More than 30 of % affected tissue, or More than 4 connidium/cm2 × ml
Contd…

55. 55
Parent and Crosses
Expected
ratio
Observed (No.)
X2 P
R S
Inoculated with race-0
Perlita FR (PFR) All R 201 0
PMR 45 All S 0 51
F1(PFR x PMR 45) All R 101 0
F2 (PFR x PMR 45) 3:1 197 58 0.69 0.3-0.3
BCs 1:1 53 49 0.16 0.7-0.5
BCr All R 87 0
Inoculated with race -2
Perlita FR (PFR) All R 101 0
PMR 45 All S 0 50
F1(PFR x PMR 45) All R 102 0
F2 (PFR x PMR 45) 3:1 139 50 0.21 0.7-0.3
BCs 1:1 128 117 0.49 0.5-0.3
BCr All R 94 0
Table 17: Segregation in progenies from crosses between resistant (R) cv. Perlita FR and
susceptible (S) cv.PMR-45 inoculation with race 0 and race 2 of s Fusarium
oxysporum f.sp.melonis in muskmelon.
Zink and Gubler, 1995 , Central America

56. 56
Table 18: Segregation for CABYV resistance in three progenies obtained
from the cross between Vedrantais and PI 124112 in Cucumis
melo. Catherine et al., 1997, France
Parents/ Crosses
No of plants Th.
Ratio
Χ2
Total R S Value Proba.
Field trial In 1993
Vedrantais 21 0 21
PI 124112 21 18 3
F1(Vedrantais X PI 124112) 21 0 21
F2(Vedrantais X PI 124112) 195 51 144 1:3 0.69 40.5
Artificial inoculation in 1994
Vedrantais 28 0 28
PI 124112 10 10 0
F1 (Vedrantais X PI 124112) 10 3 7
BC(Vedrantais X PI 124112) X
PI 124112
152 41 111 1:3 0.32 57.4
CABYV : Curcubit aphid borne yellows luteovirus Gene:cab- 1

57. 57
Field trial in 1995
Vedrantais 24 0 24
PI 124112 16 15 1
F1 (Vedrantais X PI 124112) 16 3 13
RIL (Vedrantais X PI 124112) 62 13 49 1:3 0.54
46.3
Th. Ratio- Theoretical Ratio RIL- Recombinant Inbred Lines
Contd…

58. 58
Population Resistant Susceptible
Expected
ratio
P value
Nigerian Local (NL) 5 0
Waltham Butternut
(WBN)
0 10
(WBN x NL) F1 18 0 1:0
(WBN x NL) WBN 7 16 1:1 0.064
(WBN x NL) NL 8 0 1:0
(WBN x NL) F2 71 27 3:1 0.570
Table 19: Reaction of parents, F1, F2 and backcross population from Cucurbita
moschata (Waltham Butternut x Nigerian Local) after inoculation with
watermelon mosaic potyvirus Brown et al., 2003, Costa Rica
Gene -Cmv

59. 59
Zucchini Yellow Mosaic
Virus (ZYMV)

60. 60
Population Resistant Susceptible
Expected
ratio
P value
(0.05)
Nigerian Local (NL) 5 0
Waltham Butternut
(WBN)
0 15
(WBN x NL) F1 14 0 1:0
(WBN x NL) WBN 5 5 1:1 1.000
(WBN x NL) NL 26 0 1:0
(WBN x NL) F2 129 38 3:1 0.540
Table 20: Reaction of parents, F1, F2 and backcross population from
Cucurbita moschata (Waltham Butternut x Nigerian Local) after
inoculation with Zucchini yellow mosaic virus
Brown et al., 2003, Costa Rica
Gene :Zym

61. 61Gummy Stem Blight in Watermelon

62. 62
Table 21: Response of Cucumis melo parental genotypes and intercrossed population to
inoculation with gummy stem blight (Didymella bryomiaz)
Zuniga et al., 1999, Ithaca
Pedigree Generation Number of plants Expected ratio
(R:S)
P (0.05)
R S
ZM P 0 30 0:1 …
082 p 20 0 1:0 …
890 P 26 0 1:0 …
082 X ZM F1 31 4 1:0 …
ZM X 082 F1 14 2 1:0 …
082 X ZM F2 84 21 3:1 0.31
(082 X ZM) X ZM BCs 36 35 1:1 0.92
(082 X ZM) X 082 BCr 65 0 1:0 …
890 X ZM F1 17 1 1:0 …
ZM X 890 F1 46 1 1:0 …
890 X ZM F2 63 27 3:1 0.14
(890 X ZM)X ZM BCs 40 27 1:1 0.15
(890 X ZM) X 890 BCr 54 0 1:0 …
ZM- ZPPM 339; 082- PI 157082; 890- PI 511890

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Melon necrotic spot Necrotic leaf spot on young
leaves

64. Parent or Progeny
No. of plants Expected
ratio (R:S) X2 P(0.05)
R S
Doublon 15 0 1:0
ANC-42 0 15 0:1
F1 15 0 1:0
F2 145 5 15:1 2.177 0.20-0.10
BC1 (Doublon x ANC-42) x
Doublon
150 0 1:0
Table 22: Response of Doublon, ‘ANC-42,’ and the progenies derived from their
cross to inoculation with MNSV in Cucumis melo
Gimenez et al., 2003, Spain
Gene-: Mnr 1 , Mnr 2MNSV: Melon necrotic spot virus

65. Generation
No. observed
(R:S)
No. expected
(R:S)
Fitted Ratio
(R:S)
X2 P(0.05)
Gall Index
Sumter (Ps) 0:10 0:10 All S - -
IJ-90430 (Pr) 9:0 9:0 All R - -
F1 0:18 0:18 All S - -
F2 23:73 24:72 1:3 0.06 0.82
BC1 xPs 0:19 0:19 All S - -
BC1 x Pr 8:10 9:9 1:1 0.02 0.66
Egg mass number
Sumter (Ps) 0:10 0:10 All S - -
IJ-90430 (Pr) 9:0 9:0 All R - -
F1 0:18 0:18 All S - -
F2 23:73 24:72 1:3 0.06 0.82
BC1 xPs 0:19 0:19 All S - -
BC1 x Pr 8:10 9:9 1:1 0.22 0.66
Table 23: Segregation for resistance to Meloidogyne javanica in progenies from crosses (no
reciprocals) between susceptible Cucumis sativus var. sativus Sumter and resistance
Cucumis sativus var. Hardwickii line LI 90430
Walters et al., 1997, South Carolina

66. Cucumber Mosaic
Virus (CMV)1
Zucchini Yellow Mosaic
Virus (ZYMV)
Papaya Ringspot Virus
(PRSV-W)
Cucumber Mosaic
Virus
(CMV)
Green vein banding in
watermelon leaf
(WMV2).
Alternaria leafspot
on older
watermelon leaves.

67. Methods for diseases resistance breeding
1.SELECTION
e.g. Muskmelon:
Arka Rajahans Tolerance to powdery mildew
Cucumber :
Phule Shubangi Tolerance to powdery mildew
2.INTRODUCTION
e.g. Watermelon :
Charleston Grey Resistance to Downy mildew
Cucumber :
Poinsetti USA Resistance to Downy mildew,
Powdery mildew and Anthracnose

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3.HYBRIDIZATION
e.g. Watermelon:
Arka Manik F1 (IIHR-21 x Crimson Sweet)
Resistance to Downy mildew, and powdery mildew
Muskmelon:
Punjab Hybrid F1 (M S1 x Hara Madhu)
Resistance to powdery mildew
4. MUTATION
e.g. Ridge gourd PKM-1
Induced Resistance to powdery mildew
Contd…

69. 69
Today its possible to manipulate the genome directly at the molecular
level
As a result desirable genome from wild species and other plant species
and genera can be introduced into crops which previously were
extremely difficult to improve by conventional breeding techniques
Such manipulation of genetic material is popularly referred as genetic
engineering /biotechnology
5. Genetic engineering/ Biotechnological approaches

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Transgenic plants
Transgenic plants are those carry additional stably integrated and
expressed foreign gene, usually transferred from unrelated organisms.
Gene transfer methods
1. Direct gene transfer 2.Vector mediated
 Physico-chemical uptake of DNA * Agrobacterium tumefaciens
 Pollen tube pathway * Agrobacterium rhizogenes
 Incubation of seeds with DNA * Viral vector
 Electroporation of protoplasts
 Microprojectile bombardment
 DNA injection into intact plants
eg: CMV -Cp(coat protein) gene -
Agrobacterium tumefaciens

71. (CMV&DM) Chipper X Wisconsin SMR 18 (ANTH,ALS&PM)
F1
Selfing and selection at each
Generation for 5 years
CH 18
Selfing and selection of a series of families of each
generation for 5 years
M 17
Fig 2. Pedigree of NCSU `M17’ as a selection from a family (CH 18)
in the NCSU germplasm collection
Claude and Raymon, 1982, Weslaco
Multiple disease resistance

72. (PM1, ALB) PMR 45x PI-180280 (WMV1)
2 Backcross to PMR-45 (WMV1)
Out crossed to Perlita (PM, I and 2 ALB)
(WMV1) Out crossed to Georgia-47 (DM)
Inbreeding (self and open pollination for 5 generations)
Mass selection for 10 generation
W-5
Sib crossing
Mass selection for 5 generations
Cinco (PM1&2,ALB)
(6th mass generation)
Fig 3. Pedigree of muskmelon cultivar `Cinco’Thomas and Webb, 1982

73. 73
Crops Resistance line/ verieties References
Watermelon
Fusarium wilt, anthracnose Dixielle Crall and Elmstrom(1979)
Powdery mildew ,downy
mildew and anthracnose
Arka Manik Bassett (1986)
Fusarium wilt and
Anthracnose
Charleston Grey Norton et al.,(1993)
Anthracnose and gummy
stem blight
AU Sweet Scarlet, Chalee
Au-Producer Norton et al.,1986Au-Produc
Fusarium wilt Calhoun Gray, Summit
Muskmelon
Powdery mildew, Downey
mildew
Hara Madhu, Punjab
Sunehari and Punjab Rasaila
Tamburaj and Singh
(2001)
Powdery mildew Downy
mildew, Mosaic
Mr-12, Pusa Sharabati
Cinco
Tamburaj and Singh (2001)
Thomas and Webb, 1982
Downey mildew and Viral
complex
Punjab hybrid, Mr-12 Dhiman et al., (1994)

74. 74
Cucumber
Powdery mildew,
Downey mildew
Poinsett
Tamburaj and Singh
(2001)
Anthracnose, Angular leaf
spot and Downey mildew
Palmetto, Ashley, Chinese
long stone,
M17’
Singh (2001)
Claude and Raymon, 1982,
Powdery mildew Polaris, Ambra, Yamaki Singh (2001)
Mosaic Market More Kalloo (1994)
Anthracnose
Hybrid 517 , South
Carolina
Tamburaj and Singh
(2001)
Bitter gourd
Downey mildew RHR
Tamburaj and Singh
(2001)
Summer squash
Powdery mildew Punjab Chappan Powdery mildew
Contd…

75. 75