Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
The purpose of the study was to examine Begonia from the Botanical Garden in Uppsala to
establish whether chemical analysis of fragrance from Begoniaceae can be used as a basis to
determine the pollination system.
At the time, the Uppsala Botanical garden had many different species of Begoniaceae which
served the purpose of the study.
The male and female flowers are often quite similar and there are three different ways in
which they can be pollinated:
Insect pollination- insects transfer pollen between the male and female flower,
Bird pollination- birds transfer pollen between the male and female flower,
Wind pollination- wind transfer pollen between the male and female flower.
The methods used for chemical analysis were dynamic fragrance collection, where the
fragrance is concentrated on an organic polymer, and solvent extraction of pollen and pistils
for the respective species. In addition, the number of male and female flowers during the
flowering season were counted in order to establish how they come into flower (phenology).
The Begoniaceae studied could be divided into different types according to the different
Two types of Begoniaceae were probably insect pollinated; the small, white with abundant
flowering and strong fragrance as well as the larger flowers with sweet fragrance.
One type could be bird pollinated; the type with large flowers and strong colouring without
One type was probably at least partly wind pollinated. It had male and female flowers mixed
in each raceme and no pronounced fragrance.
The results show that it is partly possible to use chemical analysis to establish how a specie is
likely to be pollinated. Chemistry gives an indication of which pollinators are likely attracted
by the type of fragrance that a flower emits but without specific pollinator studies is it not
possible to establish with certainty which pollinator.