Adaptations of flowers for pollination by different agents

Fresh or preserved specimens

Exercise : Adaptations of flowers for pollination by different agents.

Aim: To study the adaptations in flowers for pollination by different agents (wind and insects)

Principle: The process of transfer of pollen grains from the anther to stigma of a flower is called pollination.

Requirements: Fresh flowers of maize or any other cereal / gram, any insect pollination flowers like Salvia, Calotropis, Ocimum and Asteraceae flowers.

Place the given flower on a slide and observe it with the help of hand lens. Note down the adaptations of the flowers meant for pollination by the external agents.

A. Wind Pollinated Flowers - Anemophily

Diagnostic Features

·        The flowers are small, inconspicuous, colourless, odourless and nectarless.

·        Anthers and stigmas are commonly exerted.

·        Pollen grains are light, small, powdery and produced in large numbers.

·        The stigmas are large, sometimes feathery and branched adapted to catch the pollens.

B. Insect Pollinated Flowers - Entemophily

Diagnostic Features

·        The flowers are showy, brightly coloured and scented.

·        The flowers produce nectar or edible pollen.

·        Anthers and stigmas are commonly inserted.

·        Stigmas are usually unbranched and flat or lobed.