pollination, definition, types of pollination, autogamy, xenogamy, contrivances to achieve self pollination, bisexuality, homogamy, herkogamy, cleistogamy, advantages of self pollination, disadvantages of self pollination

1. Self Pollination
Dr. Sonali Randive-Aherkar

2. Pollination

3. Content:
 Introduction
 Types of pollination
 Advantages of self pollination
 Disadvantages of self pollination
 Contrivances to achieve self pollination

4. Introduction:
 Pollination is the act of transferring pollen grains
from the male anther of a flower to the female
stigma. The goal of every living organism,
including plants, is to create offspring for the next
generation. One of the ways that plants can
produce offspring is by making seeds. Seeds
contain the genetic information to produce a new
plant

5. Pollinatio
n
Self Cross
Autogamy Genitogam
y

6. Self pollination:
 Involves the transfer of pollen grains from the
anthers to the stigma of the same flower or of
another flower borne by the same plant

7. Autogamy
 Pollen from the anthers of a flower are transferred to
the stigma of the same flower.
Geitonogamy
 Pollen from the anthers of one flower are transferred
to the stigma of another flower borne on the same
plant.
 Involves two flowers belonging to the same parent
plant.
 Usually occurs with monoecious condition

9. Advantages:
 Pollen grains are not wasted.
 The purity of the generation is maintained
 Plants does not require extra energy to become
flower more attractive.

10. Disadvantages:
 New and healthier varieties are not formed.
 Results in weak progenies, producing weaker
seeds and plants.

11. Contrivances to achieve self
pollination:
 Bisexuality
Flowers should be bisexual or hermaphrodite
 Homogamy
Anthers and stigma of the bisexual flowers mature at
the same time
 They are brought close to each other by growth,
bending or folding to ensure self pollination e.g.
Catharanthus, Mirabilis, Helianthus, Solanum etc.

12.  Cleistogamy
Some plants never open to ensure complete self-pollination
e.g. Commelina, oxalis, Vigna species
Characters of cleistogamous flowers:
 bisexual small
 Inconspicuous
 colourless
 do not secrete nectar