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Tetracoccosporium   paxianum

Recognized by the cruciately septate, dark-pigmented, rough-walled  conidia borne on short conidiophores arising at right angles to the hyphaeThis dematiaceous (dark-pigmented) Hyphomycete (class) is in the  Deuteromycota (division).

Students: Note that there are no conidia floating around the field and they all seem attached to the parent hyphae.  According to my definition these are aleuriospores (aleurioconidia) produced as blown out ends of lateral hyphae.  At maturity the conidia secede with difficulty from the parent hyphae and then only by rupture of the cell that produces them (conidiogenous cell).  Thus, a characteristic of aleuriosporous fungi is that the conidia are few in number and produced singly from the conidiogenous cell.

This type of spore is obviously not very good for dispersal of the species.  Aleuriospores are often large, darkly pigmented, thick-walled and roughened.  All of these characterisitics make them good survival spores for long term peersidtence.

Question:  1. Explain why the spore characterisitcs mentioned above have survival value.

                 2. If this spore is for survival how does the fungus solve the problem of dispersal?

                        3. What common and succesful fungi produce only one spore type that functions                             for both persistence and dispersal?