parthenocarpic vegetables

2. PARTHENOCARPY:
• Null-1902-coined parthenocarpy
• Parthenos-VIRGIN, karpos -FRUIT
• Natural or artificial induction of fruit development
without pollination and fertilization is called
parthenocarpy.

4. Causes for absence of pollination
• Male sterility
• Self incompatibility.
• Adverse environmental condition.
• Absence of pollinator and pollinizer
• Dioecious

5. Mechanism of parthenocarpy
• Seed and fruit development control by phytohormones.
(Pandolfini, 2009)
• GA3, Auxin and Cytokinin involve signalling process
after fertilization for seed and fruit development.(Fos et
al., 2001)
• Increase endogenous hormones during Parthenocarpic
fruit set. (Tsao, 1980)
• Trigger the expression of auxin biosynthetic gene.
(Carmi et al., 2003)

6. Mechanism of Parthenocarpy

7. Importance of Parthenocarpy
• Increased production under adverse environment
• Seedless fruits
• Improved quality
• Off season production
• Protected cultivation
• Reduced cost of cultivation

8. Types of Parthenocarpy
1)Genetic /natural parthenocarpy
• Obligatory : unable to produce viable seeds either
in the presence or absence of fertile pollen.
Eg : Banana, pineapple and ivy gourd
• Facultative: pollination is prevented by adverse
conditions.
Eg : Tomato, brinjal and cucumber

9. 2. Artificially induced parthenocarpy
• Irradiated pollen
• Synthetic auxin
• Gibberellins

10. Methods to induce Parthenocarpy
• Breeding approaches
Conventional : Inter specific hybridization
Intra specific hybridization
Mutation
Polyploidy
• External application of PGR
• Transgenic approach

11. Conventional method:
It comprises two steps:
I. Generating a breeding population that is segregating
for the parthenocarpy trait of one parental genotype.
II. Selecting individual progeny from the segregating
population that combine parthenocarpy with desirable
traits of the non-parthenocarpic parent.

12. • Interspecific hybridization:
Solanum esculentum X solanum peruvianum
S.habrochaites X S.lycopersicum- IVT-LINE 1.
• Intraspecific hybridization:
In tomato;
 Severenien
 Oregon T5-4
 Oregon cherry

13. PGR induced parthenocarpy

14. Transgenic approach
DefH9- iaaM chimeric gene:
• DefH9-iaaM gene construct, composed of DefH9
gene from snapdragon and the iaaM coding region
from Pseudomonas syringae pv savastanoi.
• The placenta/ovule-specific expression of the
DefH9-iaaM gene confers parthenocarpic fruit
development to eggplant and tomato.

16. Tomato (Solanum lycopersicum)
Three sources - facultative parthenocarpy
• Montfavet-191 (Pat-1)
• Severianin (Pat-2)
• RP75/59 (Pat-3/Pat-4)

17. Pat-1
 Montfavet-191
 Abnormal stamens
 Higher ovary and pericarp growth
 Female sterility
 Defective pollen tube- placenta interaction
 Low seed set

18. Pat-2
 Single recessive gene
Genetic background of the recurrent parent is very
important for vigour. (Philouze et al.,1988)
 Parthenocarpic plants have determinate growth
habit.

19. Pat-3/4
 RP75/59 progeny of Atom x Budjekosoko
 Seeded fruits suppress the size of seedless fruits
 Digenic inheritance

21. Genetics of parthenocarpy
Inheritance of parthenocarpy by an Incomplete
dominant gene P.
PP(homozygous) produces parthenocarpic fruits
early(1st fruit at fifth node).
Pp(heterozygous) produce parthenocarpic fruits
later than homozygous plants
pp(recessive) produces no parthenocarpic fruits
(Pike and Peterson, 1969)

22. Parthenocarpic cucumber varieties/
lines from public sector

23. Parthenocarpic cucumber varieties

24. Parthenocarpic cucumber hybrids from
private sector

26. Maintenance of parthenocarpic
Gynoecious lines
Silver nitrate (AgNO3) - Male flowers in
gynoecious cucumbers
AgNO3 at 400 and 500 ppm
Two –three true leaf stage
Two or three times spray - Effective
(Elizabeta and Susaj, 2010)

27. • In cucumber, Gynoecy coupled with Parthenocarpy is a yield and
quality related parameter.
• The fruit will have a mild flavor, seedless and have thin skin that
doesn’t require peeling.
• In this experiment it is tested for the inheritance of Parthenocarpy in
cross of gynoecious parthenocarpic line with Indian monoecious non-
parthenocarpic line.

28. • Gynoecious line PPC-2(used as a female parent for
source of parthenocarpic gene),Pusa Uday(as male
parent)
• Resulting F1 hybrid was selfed to obtain F2 seeds and
pollinated simultaneously with P1(PPC-2) and P2(Pusa
Uday) to generate BC B1 and B2.
• The seed materials of all BC generations(B1,B2,F2)
including the parental lines and F1 were sown.
• The F2 populations comprising 213 plants were used
for genetics of parthenocarpy in background of
gynoecious and parthenocarpic inbred line PPC-2.

30. Observations:
• Plants that produced parthenocarpic fruit up to 25th node
were considered as parthenocarpic plant.
• Early parthenocarpy (1-7th node),late parthenocarpy(8th
and above) and non-parthenocarpy.
• In PPC-2 fruits seen at the lower node from the
base(early parthenocarpy)-homozygous genotype.
• Pusa Uday produced non-parthenocarpic fruit –
homozygous for parthenocarpic fruit.
• F1 hybrid produced with heterozygous condition
produced some parthenocarpic fruit (ie.5-7th node).
• F2 population,out of 213 plants, 170 produced as early
and late parthenocarpic fruit whereas 43 as non-
parthenocarpic.

32. Contd.
• The genotypes for inbred lines PPC-2 representing
parthenocarpy, non-parthenocarpy and late parthenocarpy
phenotypes were PP, pp, Pp respectively.
• It confirms that parthenocarpic trait is controlled by single
incomplete dominant gene.
• The study of F3 population shows that more than five
genes are involved in parthenocarpy whereas growing
environmental conditions and epistatic interactions
significantly influence the expression of this trait.

34. • High commercial loss- BER
• Parthenocarpy – a solution to reduce yield flushing and
to minimize BER.
• High percentage of parthenocarpy observed when
plants grown under low night temperature(8-10⁰C)-
Cochran.
• Low temperature may impair pollen fertility causing
hampered seed set and leading to the production of
seedless fruits.
• Parthenocarpic fruit obtained- GRs or low temp-
deformed fruit shape and reduced fruit size.

35. Selection of sweet pepper( Capsicum annuum)
genotypes for parthenocarpic fruit growth
Ten genotypes and Mazurka as a standard cultivar pf sweet
pepper was obtained.
Plants grown in a venlo-type glasshouse using rockwool
cubes.
Seeds sown on 23rd January and from 13th February two
different temperature set points were given: 20/20 ̊C D/N
and 20/10 ̊C D/N.

36. Results :
• For line 1 and line 3 parthenocarpic fruit % was
high at both low and normal night temperature.
• While for Lamuyo A , Lamuyo B, Gen A, Gen B
,Gen C and Bruinsma wonder parthenocarpic fruit
was observed at only low night temperatures.

38.  Reduction in percentage of Carpelloid growth was observed
at low temp. for all except for sirena RZ, Line 1 and line 3.
percentage of knots was high for all genotypes at low night
temperature, but highest for sirena RZ (56%) and lowest for
Bruinsma wonder (9%).

40. Discussion:
• Expression of parthenocarpic fruit growth clearly showed
genotypic variation.
• It was high for Line 1 and Line 3, suggesting the presence
of parthenocarpic gene(s) expressed irrespective of night
temperature.
• Most of the parthenocarpic fruit of Line 1 and Line 3 showed
carpelloid growth inside the fruit.
• These vascular strands, which are a good marker of auxin-
induced fruit development, automatically joins and forms in
such cases where the ovule is homeotically converted into a
carpel-like structure.
• However, it is not yet clear whether carpelloid growth is a
linked trait or a pleiotropic effect of parthenocarpic gene(s)
or that some other physiological or molecular change leads
to this malformation.

41. contd.
• A high percentage of knots or pseudo-fruits was found for all
genotypes, except for Bruisma Wonder, at low night
temperature , where most likely the non-viability of pollen
increased the percentage of unfertilized fruit.
• It has been reported that unfertilized fruit has poor sink
strength (Nielsen et al., 1991) and deformed fruit shape
(Rylski, 1973; Bosland and Votava, 1999) as compared to
fertilized ones.
• Also Rylski (1986) reported that seedless fruits produced at
low night temperature reached only half to one fourth of the
weight of the corresponding fertilized ones

42. contd.
• Thus they concluded that high expressivity of parthenocarpy
was observed for line 1 and line 3; however carpelloid
growth appeared in these lines.
• Bruinsma Wonder-low percentage of knots and also minor
differences in fruit weight and shape between seedless and
seeded fruits at low night temperature.
• Therefore Bruinsma Wonder is candidate genotypes for
further research and is proposed to be used in a breeding
program for introgression and modulation of
parthenocarpy in existing commercial pepper cultivars

44. • First reported by Dr.Kihara(1939), succeed in
producing commercial triploid.
• Diploid pollen on triploid stigma stimulates
parthenocarpy, but ovules fail to develop.

47. Pedigree of hybrid “Anominori”