Botryodiplodia sp. - Crops for the Future

Characteristically for this fungus is the generation of pycnidia in which the spores of the
fungus are formed. Pycnidia develop on artificial media only rarely and after a long time. But
if they are generated they can be seen with the naked eye as black balls of the size of a
pinhead.
The spores are elliptical and compared to other spores relatively big. Young, immature spores
are colourless and unicellular whereas mature spores are brown coloured, distichous and
thick-walled (Figure 12). Only the presence of the mature spores allows a proper
identification of the fungus.
The fast and constantly growing mycelium of the fungus is snow-white at first, turning its
colour within three to four weeks black (Figure 13). This discolouring is not due to the
generating of the spores.
The most important species of the genus is Botryodiplodia theobromae.
Figure 12: Mature and immature spores of Botryodiplodia sp.
Figure 13: Petri-dishes with Botryodiplodia sp. after seven days (left)
and after four weeks (right)
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