Pollination
agents – insects, birds and bats !!
Insect Pollination
E.g., bees, moths, butterflies
It is the most sure and least wasteful method. Insects, visit the flowers not to effect pollination but to collect nectar, edible pollen or for shelter. As the insect visits a flower, its body gets dusted with pollen grains. When the loaded insect visits another flower, its body brushes against the stigma and inadvertently transfers the pollen to it bringing about pollination.
It is the most sure and least wasteful method. Insects, visit the flowers not to effect pollination but to collect nectar, edible pollen or for shelter. As the insect visits a flower, its body gets dusted with pollen grains. When the loaded insect visits another flower, its body brushes against the stigma and inadvertently transfers the pollen to it bringing about pollination.
Some of the
characteristic features of insect pollinated flowers are
·
The flowers are large, conspicuous and brightly
coloured.
·
When flowers are small, they aggregate in the
form of inflorescence.
·
The flowers have a pleasant fragrance and sweet
nectar.
·
Pollen grains are usually rough and sticky and
often show spinous outgrowths.
Bird Pollination
The common bird pollinators are
humming birds, sun – birds and honey – eaters. Birds can obtain only one staple
food from flowers and that is nectar. The bird pollinated flowers have funnel –
shaped or tubular corollas which are brightly coloured. The floral parts are
commonly leathery and they produce copious amount of nectar and large
quantities of pollen which are sticky.
Common bird – pollinated plants
are Bombax (red silk cotton), Erythrina (coral tree) Bigonia, Lobelia, Agave.
Bat Pollination
Bats bring about pollination
only in the tropics. Bats are nocturnal animals and the flowers they visit are
large and emit a strong odour. They move very fast and transport pollen to long
distances. Bat pollinated flowers generally produce more nectar than ornithophilous
flowers. They also have a large number of stamens.
No comments:
Post a Comment