Androecium is the third whorl which represents the male reproduction organ of the flower. It is made up of one or more stamens or microsporophylls. Stamen (An individual member of the androecium) consists of Filament and Anther. The slender stalk of the stamen which bears the anther at its tip is known as Filament. Each Stamen has usually a filament, anther and connective. Each anther consists of two lobes and each lobe consists of two chambers or loculi, which are called the pollen-sacs or microsporangia. Thus, there are four pollen sacs in each anther. Each pollen sac produces a large number of pollen grains/microspores. The pollen grains or microspores are the male gamets.
Some Descriptive Terms of The Androecium
Dithecous: - Anther with two loculus.
Monothecous: - The anther which has only one locule (in some case).
Androphore: - Androecium bearing stalk.
Staminode: - A rudimentary stamens which does not bear fertile pollen grains E.g:-Stellaria.
Polyandrous:-Androecium which consists of free stamens is known as Polyandrous. E.g:-Poppy, papaver.
Monadelphous: - With free anthers the filaments of stamens which are united into a single handle or tube is known as Monadelphous. E.g:- China rose.
Diadelphous: - With free anthers the filaments of stamens which are fused together to form two bundles is known as Diadelphous. E.g:-Pea.
Polyadelphous: - With free anthers the filaments of stamens which are united to form a number of bundles is known as Polyadelphous. E.g:- Citrus.
Syngenesious: - Stamens untied by their anther but the filaments are free is known as Syngenesious. E.g:- Sonchus, sunflower.
Synandrous: - Stamens united throughout their whole length (anther and filament). E.g:-Cucurbita.
Epipetalous: - Stamens more or less fused with petals and appearing to originate from them. E.g:- Ocimum, Solanum.
Epitepalous: - Stamens bore on the tepals. E.g:- Asphodelus.
Gynandrous: - Stamens fused with the carpels. E.g:- Calotropis.
Inserted: - Stamens shorter than corolla tube. E.g:- Ixora
Dithecous: - Anther with two loculus.
Monothecous: - The anther which has only one locule (in some case).
Androphore: - Androecium bearing stalk.
Staminode: - A rudimentary stamens which does not bear fertile pollen grains E.g:-Stellaria.
Polyandrous:-Androecium which consists of free stamens is known as Polyandrous. E.g:-Poppy, papaver.
Monadelphous: - With free anthers the filaments of stamens which are united into a single handle or tube is known as Monadelphous. E.g:- China rose.
Diadelphous: - With free anthers the filaments of stamens which are fused together to form two bundles is known as Diadelphous. E.g:-Pea.
Polyadelphous: - With free anthers the filaments of stamens which are united to form a number of bundles is known as Polyadelphous. E.g:- Citrus.
Syngenesious: - Stamens untied by their anther but the filaments are free is known as Syngenesious. E.g:- Sonchus, sunflower.
Synandrous: - Stamens united throughout their whole length (anther and filament). E.g:-Cucurbita.
Epipetalous: - Stamens more or less fused with petals and appearing to originate from them. E.g:- Ocimum, Solanum.
Epitepalous: - Stamens bore on the tepals. E.g:- Asphodelus.
Gynandrous: - Stamens fused with the carpels. E.g:- Calotropis.
Inserted: - Stamens shorter than corolla tube. E.g:- Ixora
Exerted: - Stamens longer than corolla tube projecting beyond the petals. E.g:- Passion flower.
Basifixed: - Filament attached to the base of the anther. E.g:- Mustard.
Dorsifixed: - Filament attached to the dorsal side of the anther. E.g:- Bauhinia.
Adnate: - Filament attached to the anther throughout its length. E.g:-Michelia.
Versatile: - Filament attached to the back of the anther at a point only. E.g:- Grasses.
Introse: - Anther facing inward. E.g: - Hibiscus, Dianthus, solanum.
Extrose: - Anther facing outward from the center of the flower. E.g:- Argemone.
Basifixed: - Filament attached to the base of the anther. E.g:- Mustard.
Dorsifixed: - Filament attached to the dorsal side of the anther. E.g:- Bauhinia.
Adnate: - Filament attached to the anther throughout its length. E.g:-Michelia.
Versatile: - Filament attached to the back of the anther at a point only. E.g:- Grasses.
Introse: - Anther facing inward. E.g: - Hibiscus, Dianthus, solanum.
Extrose: - Anther facing outward from the center of the flower. E.g:- Argemone.
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