This document discusses parthenocarpy, or fruit development without fertilization, in vegetable crops. It defines parthenocarpy and lists some common causes for lack of fertilization. The mechanism is controlled by plant hormones like gibberellins and auxins. Parthenocarpy is important for increased and off-season production and reduced costs. There are two main types - genetic/natural and artificially induced. Breeding approaches, plant growth regulator application, and transgenic methods can be used to induce parthenocarpy. Specific examples are provided for tomatoes, cucumbers, peppers, watermelons, and eggplants.

1. PARTHENOCARPY IN VEGETABLE CROPS
PARTHENOCARPY:
• Null-1902-coined parthenocarpy
• Parthenos-VIRGIN, karpos -FRUIT
• Natural or artificial induction of fruit development without
pollination and fertilization is called parthenocarpy.
Causes for absence of pollination:
• Male sterility
• Self incompatibility.
• Adverse environmental condition.
• Absence of pollinator and pollinizer
• Dioecious
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)

2. Importance of Parthenocarpy:
• Increased production under adverse environment
• Seedless fruits
• Improved quality
• Off season production
• Protected cultivation
• Reduced cost of cultivation
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
2)Artificially induced parthenocarpy
• Irradiated pollen
• Synthetic auxin
• Gibberellins
Methods to induce Parthenocarpy:
• Breeding approaches
 Conventional : Inter specific hybridization
Intra specific hybridization
 Mutation
 Polyploidy
• External application of PGR
• Transgenic approach

3. 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.
• 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
PGR induced parthenocarpy:

4. 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.
TOMATO
Three sources - facultative parthenocarpy
• Montfavet-191 (Pat-1)
• Severianin (Pat-2)
• RP75/59 (Pat-3/Pat-4)
Pat-1
• Montfavet-191
• Abnormal stamens
• Higher ovary and pericarp growth
• Female sterility
• Defective pollen tube- placenta interaction
• Low seed set
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.
Pat-3/4
• RP75/59 progeny of Atom x Budjekosoko

5. • Seeded fruits suppress the size of seedless fruits
• Digenic inheritance.
CUCUMBER
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.
Parthenocarpic cucumber varieties/ lines from public sector:
Parthenocarpic cucumber hybrids from private sector

6. 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
CAPSICUM:
 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(8-10⁰ C)-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.
WATERMELON
 First reported by Dr.Kihara(1939), succeed in producing
commercial triploid.
 Diploid pollen on triploid stigma stimulates parthenocarpy, but
ovules fail to develop.

7. BRINJAL:
Pedigree of hybrid “Anominori”