Pollination and Fertilization
Pollination:
Pollination is defined as the placement or transfer of pollen from the anther to the stigma of the same flower
or another flower. In gymnosperms, pollination involves pollen transfer from the male cone to the female
cone. Upon transfer, the pollen germinates to form the pollen tube and the sperm for fertilising the egg.
Pollination is a very important part of the life cycle of a flowering plant. It is part of the sexual reproduction
process of flowering plants, which results in seeds that will grow into new plants. Flowers are the structures
of flowering plants that contain all the specialised parts needed for sexual reproduction.
Pollination takes two forms:
1. Self-pollination.
2. Cross-pollination.
Self- Pollination:
The transfer of pollen grains from the anther of a flower to the stigma of the same flower or another flower
on the same plant is called self-pollination.
Conditions Favouring Self – Pollination:
▪ Bisexuality, monoecious: Bisexual, monoecious plants have both male and female reproductive parts on
the same plant.
▪ Homogamy: The anther and stigma of a bisexual flower mature at the same time.
▪ Cleistogamy: The pollen grains pollinate the stigma of the same flower. In this case, the flowers never
open.
Advantages of Self – Pollination:
▪ Pollination is guaranteed.
▪ No energy spent on producing showy petals, scent or nectar or a large number of pollen grains.
▪ Desired parental characteristics are retained.
Disadvantages of Self – Pollination:
▪ Weakening of species due to inbreeding, undesired traits cannot be eliminated.
Pollination:
Pollination is defined as the placement or transfer of pollen from the anther to the stigma of the same flower
or another flower. In gymnosperms, pollination involves pollen transfer from the male cone to the female
cone. Upon transfer, the pollen germinates to form the pollen tube and the sperm for fertilising the egg.
Pollination is a very important part of the life cycle of a flowering plant. It is part of the sexual reproduction
process of flowering plants, which results in seeds that will grow into new plants. Flowers are the structures
of flowering plants that contain all the specialised parts needed for sexual reproduction.
Pollination takes two forms:
1. Self-pollination.
2. Cross-pollination.
Self- Pollination:
The transfer of pollen grains from the anther of a flower to the stigma of the same flower or another flower
on the same plant is called self-pollination.
Conditions Favouring Self – Pollination:
▪ Bisexuality, monoecious: Bisexual, monoecious plants have both male and female reproductive parts on
the same plant.
▪ Homogamy: The anther and stigma of a bisexual flower mature at the same time.
▪ Cleistogamy: The pollen grains pollinate the stigma of the same flower. In this case, the flowers never
open.
Advantages of Self – Pollination:
▪ Pollination is guaranteed.
▪ No energy spent on producing showy petals, scent or nectar or a large number of pollen grains.
▪ Desired parental characteristics are retained.
Disadvantages of Self – Pollination:
▪ Weakening of species due to inbreeding, undesired traits cannot be eliminated.
