Its my my first seminar topic ,,so my curiosity can be clearly seen .. points on parthenogenesis ,its types ,methods to develop a parthenocarpic fruit .Hope may helpful to some extent ,,,Thank you

1. :SEEDLESS FRUITS

2. ._definition by nitsch (1965)
: Formation of fruits without fertilisation.
,Absence of seeds.

3. ▪ 1:Natural parthenocarpy_ bananas which known to develop naturally..
▪ 2:Induced parthenocarpy_fruit formation is stimulated.
▪ Based on stimulating factors,;
▪ *Genetical parthenocarpy
▪ . *Environmental parthenocarpy
▪ . *Chemical parthenocarpy
▪ BASED ON POLLINATION
▪ Vegetative parthenocarpy/Autonomous:The fruit development without pollination.
▪ Eg...banana
▪ Stimulative/aitonomous parthenocarpy:The fruit development with pollination.

4. CONDITION FOR PLANT TO PRODUCE PARTHENOCARPICFRUIT
*Fruit develop after fertilisation.then sometimes the seed stop
development and result in seedless fruit.eg-grapes
*Pollination as usual and pollen tube grow to certain distance but fruit
develop without fertilisation.eg-nicotiana.
*Dead pollen or non viable pollen placed on stigma encourages fruit
formation.
*Fruits may be developed without pollination.eg-tomato,banana,fig.
THUS PARTHENOCARY IS AN NATURAL ACCIDENT OR IT CAN BE
INDUCED ARTIFICIALLY BY THE HELP OF HORMONE LIKE AUXIN AND
GIBBERELLINS.

5. GENETICAL PARTHENOCARPY
*Common in cultivated than in wild plants.
*Mutations,hybridization,incompatibility are the reasons.
*In incompatible plants ,pollen tube growth is extremely slow and flowers fall much before the tube
reaches the ovary.
• In natural genitical parthenocarpy,is associated with high auxin content and are triploids.eg-grapes.

6. • Incomplete dominant gene P
• In homozygous condition PP produces non
parthenocarpic fruits.
• Heterozygous Pp produces parthenocarpic fruits.

9. ▪ Climatic factors like fog , temperature particularly nocturnal temperature.
▪ The low temperature slows down pollen tube growth and pollen tube fails to reach the ovary.
▪ Some of the varieties of pears and apples are parthenocarpic in South Africa while seeded in
USA.
▪ In cucurbits pepo,preventing the pollination factor and subjecting the plant to 15 c during
night can induces parthenocarpy.
▪ Low temperature and short day promote pistillate flowers in cucurbits and inhibits flower
abscission in tomato and thereby promote parthenocarpy.

10. ▪ Gustafson (1939)made a comparative study of hormone in seeded and seedless fruits and
found that seedless varieties have bigger auxin ccontent.
▪ Application of auxin:
*prevent abscission layer and encourage the development of vascular system in the stalk.
*Auxin brings abortion of seeds.
*Auxin spray also reduces loss of water from fruits.
* Starch synthesis is increased.
*Effect enzymatic activity and increase oxygen uptake.
* Vegetative parthenocarpy can be induced in morus alba if pollination is prevented
through bagging.

11. Application of gibberellin
*GA3 if injected in ovary of zephyranthes would stimulate the
development of ovaries with seeds but without embryos.
* Low concentration of gibberellin (20ppm) can induce
parthenocarpy.
• Induces seedless fruits in tomatoes,figs,apples,pears.
• Both 2-NOA(2-naphthoxy acetic acid) and 24D can induce fruit
formation in tomato if the same fails to grow in low temperature.

12. PARTHENOGENESIS
*Kerner (1976) in Antennaria alpina,staminate flowers are present
fertile pollen are very few.
*In this plant, megaspore mother cell directly functions as
megaspore without meiosis and diploid megaspore directly
develops to embryo without fertilisation.
• This kind of development of embryo without fertilisation is termed
as parthenogenesis.
• Haploid parthenogenesis
• Diploid parparthenogenesis
• Facultative parthenogenesis
• Induced parthenogenesis

13. # In haploid parthenogenesis,the egg is formed after reduction division of
mega spore mother cell and develops to embyo.As it contain only a single set
of chromosomes it cannot establish it’s generation.
# Diploid embryos may be formed without fertilisation if megaspore mother
cell develops to megaspore directly.this is called diploid embryogenesis.
# Development of embryo is only a chance is included in facultative
embryogenesis.reported in orchis maculata.
#A number of physiological and chemical treatment for induced
parthenogenesis like,~exposing ovary to low /high temperature soon after
pollination,~exposing stigma to x-rayed pollen,~using pollen of unrelated
plants or delayed pollination,~chemical treatment.
Eg:Tritium monoccum.

14. METHODS FOR THE INDUCTION OF PARTHENOCARPY
*Interspecific and intergeneric crosses are responsible for the parthenogenesis in Brassicas.
*Delayed pollination will help to obtain haploid embryos
*Use of chemical Belvitan in petunia violaceae result in enlargement of micellar cells and
formation of pro embryos.
*When applying the growth regulator it must be penetrate the cuticle or tissues so esters are
effective.
*Fumigation with ester vapour possible only in green houses.
*In pears frost injury of ovary is beneficial
*treatment of grapes floral clusters,dipping in GA3 is useful in large scale production in Japan.
*In strawberry,2NAA at concentration of 50mg/l sprayed after two weeks of pollination.
* Artificial changes in temperature is also successful.

15. SIGNIFICANCE OF
PARTHENOCARPY/ECONOMICAL
IMPORTANTANCE
Parthenocarpic fruits are required by food
preservationist for making
jams,jellies,sauces,fruit drinks etc.because
the edible fleshy part of fruit may increased
by the absence of seeds.
😊Helps the growers to keep the insect and
pest away because there no need for
pollinating agent.So it improves the crop
yield without using pesticides.
,😀 Preferred by consumers.
😀 Plants need not to be pollinated.

20. ▪WHY SOME FRUITS
DEVELOP
PARTHENOCARPICALY
IN NATUREWHILE
OTHERS DO NOT?