1. 7/14/2021 1
Department of Botany JES.College, Jalna
By
Mr. Yogesh Urdukhe
Department of Botany JES College Jalna
2. Structure of flower
Flower is modified shoot
To attract pollinators with colorful petals, scent,
nectar and pollen
7/14/2021 2
Department of Botany JES.College, Jalna
3. Reproductive floral organs: female
Carpel or pistil – female reproductive organs
Stigma – is where pollen sticks to
Style – is the long tube that connects stigma to ovary
Ovary – enlarged structure at the base of carpel/pistil where the ovules are located;
it will become the fruit.
Ovules – contains female
gametophyte, becomes
the seed
carpel
or
pistil
ovary
7/14/2021 3
Department of Botany JES.College, Jalna
4. Reproductive floral organs: male
Stamen – male floral organ, consists of:
Anther – part of the stamen that produces pollen
Filament – stalk-like structure that holds anther
Pollen – immature male gametophyte
7/14/2021 4
Department of Botany JES.College, Jalna
5. Non-reproductive floral organs
Petals – whorl of flower organs that are often brightly colored to attract
pollinators
Corolla – whorl of petals in a flower
Sepals – whorl of leaf-like organs outside the corolla; help protect the
unopened flower bud.
Calyx – whorl of sepals in a flower
Tepals – when sepals and petals look the same
7/14/2021 5
Department of Botany JES.College, Jalna
6. Transfer of pollen from anther to stigma
Pollination
7/14/2021 6
Department of Botany JES.College, Jalna
7. Why is pollination important?
Sexual reproduction is important for evolution:
Sexual reproduction produces variable offspring,
creating diversity and variation among populations
(shuffling of genes)
You need variation for Natural Selection to occur
Sexual reproduction is advantageous to an organism
only if it happens with someone other than itself!
Outbreeding = good! (inbreeding = bad…)
7/14/2021 7
Department of Botany JES.College, Jalna
8. Types of pollination
Self pollination (Autogamy)
Cross pollination
Geitoanogamy : Pollination has occurred between two flower on the
same plant
Xenogamy : Pollination has occurred between two flower on the
different plant
7/14/2021 8
Department of Botany JES.College, Jalna
9. Mechanism for Self-polliation
Bisexual flower
The flower which achieve anther dehiscence and receptive stigma
simultaneously
Cleistogamy :- Commelina benghalensis ,
In family Malvaceae the androecium is monoadulphous having
staminal column and the capited stigma project beyond the staminal
column
7/14/2021 9
Department of Botany JES.College, Jalna
10. Mechanism Cross pollination
Self sterility – Inabilaty of pollen to germinate on it’s own stigma
Dichogamy - The maturation time of male and female is different
Herkogamy – Structure of male and female sex organs itself proves a
barrier to self-pollination. Stigma projects beyond the stamen
(Caryophyllus) or anther dehisce at a distance from its own stigma
(Gloriosa ) , pollene remain aggregated in pollinia (Orchids)
Heterostyly - Difference in the length of style and the length of stamen
7/14/2021 10
Department of Botany JES.College, Jalna
12. Vector / Agencies
Anemophily: Transfer of pollen by wind
Adaptation in male flower
Plant bears small and inconspicuous flower
Perianthe lobes absent
Pollene grains are small, light , smooth and dry
Adaptation in female flower
Stigma must be large and feathery , brush like
It having considerable area to catch the pollen
7/14/2021 12
Department of Botany JES.College, Jalna
14. Hydrophily :
Transfer of pollen by water
Hypohydrophily – it includes plants which are pollinated in side the water
eg.- Ceratophyllum, Najas and zostera .
Epihydrophily - it includes plants which are pollinated on the surface of the water
eg.- Vallisneria spiralis
Entomophily :
Transfer of pollen by water i.e. Bees, Flies, Waps, Moths and Betles
Bees contributes up to 80% of all pollination done by insect
Brightly coloured
Sweet fragrance or unpleasant smell
Produce Nectar
E.g Salvia, Refflesia, Aristolochia, Yucca, Ophrys speculum
7/14/2021 14
Department of Botany JES.College, Jalna
18. Why do animals pollinate plants?
They get a REWARD: food! In
exchange for moving their pollen
to another flower
Nectar – a sugary solution produced
in special flower glands called nectaries
Nectar concentration matches energy requirements of the pollinator: bird-
and bee-pollinated flowers have different sugar conc.
Pollen – is high in protein, some bees and beetles eat it.
Flowers can produce two kinds of pollen: a normal and a sterile, but tasty,
kind, for the insect.
7/14/2021 18
Department of Botany JES.College, Jalna
19. Getting the pollinator’s
attention
Plants advertise their pollen and nectar rewards
with
Colors – bees see blue, yellow, UV; while birds see
red. Bats don’t see well, so flowers are white.
Nectar or honey guides –
a visual guide for pollinator
to locate the reward (pansy flower)
Aromas – for insects, nectar.
Can also be carrion or dung smell
7/14/2021 19
Department of Botany JES.College, Jalna
20. Plant Mimicry
Some plants take advantage of the sex drive of certain insects…
Certain orchids look like female wasps, and even smell like them!
Males try to mate with them,
and in the process they
pollinate the plant
The orchid gets pollinated,
but the male wasp only gets
frustrated!
7/14/2021 20
Department of Botany JES.College, Jalna
21. Ornithophily :
Pollination by Birds i.e. Humming bird, Sun bird, honey eater bird
Characteristics of ornithophilous flower are
Tubular , cup shaped or urn- shaped flower
Bright colour
Large quantities of pollen
Plenty of nectar
The pistil and stamens usually project beyond the perianth lobe
E.g Nicotiana glauca , Callistemon ,Strelitzia reginae
7/14/2021 21
Department of Botany JES.College, Jalna
24. Cheiropterophily
Pollination by Bat
Characteristics of Cheiropterophilous flower are
Flower born singly or in cluster with long stalk quite away from foliage
and branches
The flower opens only at or after dusk
On blooming flowers emites a strong odour
They produce quantities of nectar
E.g Mucuna gigantea, Adansonia digitata, Kigelia africana
7/14/2021 24
Department of Botany JES.College, Jalna