Differentiation
of
Pollen - An anther or pollen has two distinct morphologies which have the potential to develop into two different types of generations gametophyte and sporophyte. This is referred to as pollen dimorphism.
The pollen capable of forming haploids (embryogenic pollen) is small with a cytoplasm that stains less intensely with acetocarmine than does gametophytic pollen. Such pollen is usually low in quantity and accounts for a very low frequency of haploid formation. Exposure of plants to low temperatures before flowering increases the frequency of embryogenic pollen.
