Characteristics, advantages and disadvantages of self-pollination

Introduction

• Self Pollination


• Cross Pollination

Self Pollination

Adaptation for self-pollination

1. Homogamy : Homogamy is the condition in which flowers are bisexual anther and stigma mature at the same time to make self-pollination possible. Under such a condition the stigma receives the pollen grains from the anthers of the same flower by the agency of wind or insects. E.g., Mirabilis, Ixora, Sunflower, etc.


2. Cleistogamy : There are some bisexual flowers, which never open. They are small and sometimes inconspicuous and remain closed. The pollen grains, therefore, may only pollinate on the stigma of the same flower. Such a condition is called cleistogamy and the flower are called cleistogamous flowers. E.g., Commelina benghalensis, Impatiens (Balsam), Arachis hypogea (Groundnut), etc.
   

Characteristics of self-pollinated flowers

• Self-pollination occurs between anther and pistils of the same flower or different flowers of the same plant.


• Presence of bisexual flower or monoecious plants are must for self-pollination.


• Flowers are generally small, less attractive and without nectar.


• Less number of pollen grains are required.


• Seed Produced through self-pollination are small, light in weight and less in number.


• Progenies of self-breeding plants exhibit less vigour. Sometimes they are weak.


• Newer qualities other than parents never develop.


• Progenies show almost nil variation which is essential for evolution.


• Plants produced show genetical purity.


• Self-pollination increases homozygosity among plants.


• Chances of pollination is 100 percent in self-pollinated plants.

Advantages of self-pollination

• A very few pollen grain can pollinate the flower.


• Purity of the race is maintained.


• Self-pollination avoid wastage of pollen grains.


• Less chances of failure of pollination.

Last words

• Self-pollinated flowers have small, light weighted and fewer numbers of seeds.


• Continuous self-pollination results in the production of weaker progeny.


• there are no chances of the production of new species and varieties of plants.


• The chances of evolution is also reduced.