Tomato

Floral biology and breeding techniques

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2. •Scientific Name:Lycopersicon esculentum Mill.
•Family : Solanaceae
•Chromosome No.: 2n = 2x= 24
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3. •Even though it is consumed
in the ripened stage it is
considered as a vegetable
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4. •2
nd
most consumed vegetable after potato in the
world
•1
st
in terms of total contribution of nutrients to
human diet among vegetables
•Consumed in fresh form and various processed forms
like soup, sauce, ketchup, paste, puree, canned etc.
•Tops the list of processed vegetables
•Also an ideal model plant for physiological,
biochemical, cytological and molecular investigations
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5. •Cultivated all over the world
•Area : 4643957 ha
•Production : 129942416 MT (FAO, 2007)
•Leading countries are USA, Russia, Italy, China,
India, Turkey, Egypt, Spain, Greece, Brazil, and
Mexico
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6. •Originated in the New World (South America)
specifically to the Andean region encompassed by
parts of Chile, Columbia, Ecuador, Bolivia and
Peru.
•Domestication in Mexicoby the Indians
•Immediate ancestor : L. esculentum var.
cerasiforme (wild cherry
tomato)
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7. •After Spanish conquest of South America spread
to Europe, USA and the rest of the world
•Concomitant gradual evolution of the large
fruited types and shift from allogamy to
autogamy under domestication
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8. •L. esculentum
•L. pimpinellifolium
•L. cheesmani
•L. hirsutum
•L. pennellii
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•L. chmielewskii
•L. parviflorum
•L. chilense
•L. peruvianum

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FLORAL
BIOLOGY
FLORAL
MORPHOLOGY
FLORAL
ANTHESIS

10. •Extra-axillary cyme with
dichotomous or
polychotomous branching
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11. •Ebracteate, bright yellow,
chasmogamous, pentamerous,
actinomorphic, hypogynous,
hermaphrodite, with pistil
enveloped by a solid tube
formed by the stamens
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12. •5 sepals
•United
•Often persistent
•Possesses trichomes
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13. •Bright yellow
•5 petals
•Gamopetalous
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14. •5 stamens
•Epipetalous
•Small filaments
•Large anthers
•Stamens form a solid
cone enclosing the pistil
•Anther dehiscence is
introselylongitudinal
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15. •Ovary -superior,
bicarpellory &
syncarpous
•Style -Single
•Stigma -Bilobed
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Stigma
Style
Pores
Petal
Calyx
Ovary
Ovule
Tip of Pistil
Tube of Fused
Anthers

18. •Starts in morning around 6 am and continues till
11 am
•Maximum flower opening –7 to 9 am
•Stigma receptivity –16 to 18 hrs before anthesis
to 5 to 6 days after anthesis
•Pollen viability –2 to 5 days (18 -25°C) & upto 6
months in a dessicator (5°C)
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19. •Essentially a Self Pollinated
crop as stamens form a solid
cone enclosing the pistil
•Self pollination varies
between 94 -99%
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•But 1.5 –47% Natural Cross pollinationhave
been reported depending on
–Temperature
–Insect population & activity at flowering time
–Planting design
–Plant population
–Wind velocity & direction
–Genotypic nature

21. •Maximum if pollination is at the time of anthesis
•Fertilization occurs 24 to 50 hrs after pollination
•6 to 8 weeks from first flower to ripe fruit
•Fruit is a berry
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22. •Bagging of young bud
•Manual transfer of freshly collected pollen on
stigmas of flowers of the same plant
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23. •Includes
–Emasculation
–Pollen collection
–Artificial pollination
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24. •Select a bud in which
anthesis will commence 12
-16 hours later
•Petals just out of the bud
•Corolla colour is slight
yellow or even paler
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25. •Removal of organs
from flower of
parent
•Use sharp-pointed
forceps to force open
the selected buds
•Then split open the
anther cone
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26. •Grasp the anther cone with
forceps with one tip inserted
between style & anther and
the other between anther
and calyx
•Gently pulling away from
the floral axis carefully
remove the anther cone out
of the bud, leaving the
calyx, corolla and pistil
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27. •Or the stamens can also be
removed individually
•Bag the emasculated flowers
•Normally emasculation is
done in the afternoon and
pollination in the next
morning
•To avoid emasculation CGMS
or GMS lines can be used
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Emasculated Flower

28. •Collect flowers from the male
parent during early morning
hours
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•Remove the anther cones
from the flowers and put
them in glassine
envelopes

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•Dry the anthersby
placing the envelopes
30 cm below a 100-watt
lamp for 24 hours. The
temperature is around
30ºC

30. •Put the dried anther cones in a
plastic cup. Cover the cup with a
fine mesh screen (200-300 mesh)
and then seal it with a similar
tight-fitting cup, serving as a lid
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•Shake the cup about 10-
20 times so that the
pollen is collected in the
“lid” cup.

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•Transfer the pollen into a small
suitable container for pollination.
Fresh pollen is best for good
fruit-set. It can be kept for one
day at moderate room
temperature
•Or can be placed in dehydrator with silica gel &
kept in a refrigerator at 10°C to maintain
viability for 10 -15 days

32. •Tap or vibrate the flower to release the pollen
and collect it in a glass tube
•Or use a flattened dissecting needle or forceps to
gather pollen by cutting a slit in the anther cone
and scraping the contents of one antheridia at a
time
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•On complete
blossoming of the
emasculated flowers
cut their calyx and
corolla to expose the
stigma

34. •Dip the stigma into the
pool of pollen in the
pollen container
•Or pollinate by touching
the stigma with the tip of
the index finger dipped
in the pollen pool
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35. •Freshly collected pollen can also be applied with
a camel hair brush or by using a pollination
syringe
•Hybridized flowers are tagged properly
•Pollination is usually done 3 times weekly on
alternate days over a 3-5 week period depending
upon rate of flower development
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36. •Successful pollination results in
ovary enlargement within 4 -5
days
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•Success rate -50 to 70%
•Depends upon temperature and humidity
•22 -28°C and 70 -80% RH are optimum for good
seed set
•Pollinate only first 3 -4 flowers in each
inflorescence as basal flowers set seeds better
than terminal ones

37. •Hybrid fruit can be
recognized by the cut
sepals
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