Leaf colour patterns, vegetative and sexual reproduction of Episcia ...

Anthesis
The term “anthesis” describes the whole period in which a flower is active i.e. as long as
pollen is presented and/or the stigma is receptive. The flowers of Episcia lilacina are proteandrous.
Male and female stages proceed separately. This chapter deals with the process of Episcia lilacina’s
anthesis.
Materials and Methods: The process of anthesis was documented using the same plants
and methods as in the last chapter. To assure the receptivity of the stigma, potassium
permanganate (KMnO 4 ) was dissolved in water. This solution was transferred to the stigma,
which in case of receptivity should turn black. Unfortunately the stigma turned black every time
as soon as it came in contact with KMnO 4 . Receptivity was efficiently measured via observation
because of the swelling of the stigma lobes.
Results: The male stage (Fig. 27, left) of anthesis starts between four and five o’clock in the
morning. Shortly after the opening of the flower the release of pollen begins. The four anthers
open and the pollen is presented freely accessible.
Between four and five o’clock in the afternoon the filaments coil. The stigma is still
immature. The style has not reached its full length. Thus the male stage comes to an end. In the
course of the next hours the style grows in length so that the stigma reaches the location that was
held before by the anthers. During this growth the stigma becomes receptive. The female stage
(Fig. 27, right) begins in the subsequent night between midnight and four a.m. and lasts one or
two days. The end of the receptivity of style is signified by shrivelled stigma lobes. The corolla
detaches itself and drops. The style stays prominent for a few days and withers afterwards. If a
successful pollination took place a growth of fruit becomes recognizable after around three days.
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