Introduction to Fungi, Third Edition

SCLEROTINIACEAE
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Fig15.6 Life cycle of Botryotinia fuckeliana (anamorph Botrytis cinerea).Innature,thisfungusoverwintersbymeansofsclerotia
which may germinate in either of two ways.Conidiogenic germination gives rise to the macroconidial state which can be formed also
from mycelium.The blastic macroconidia are multinucleate, as are mycelial segments. Phialidic microconidia are formed from
vegetative mycelium or from macroconidia.They are uninucleate, serving mainly as fertilizing agents for sclerotia of opposite mating
type.Fertilization leads to carpogenic germination of a sclerotium, i.e. to the formation of apothecia, resulting in eight uninucleate
ascospores of either of two mating types.The diploid state is confined to the tip of the ascogenous hypha (not shown; see Fig. 8.10).
Open and closed circles represent haploid nuclei of opposite mating type. Key events in the life cycle are plasmogamy (P),
karyogamy (K) and meiosis (M).