Since its discovery in the late 1920’s, there has been no apparent sexual state of P. chrysogenum.  However, based on DNA sequencing researchers believe that if a sexual state is seen, it will resemble that of ascomycota organisms.  Ascomycetes produce sexual spores called ascospores which are contained in a sac-like structure called an ascus. Because P. chrysogenum lacks this sexual structure, the only known mode of reproduction is through asexual spores.

The P. chrysogenum reproduction path resembles the right portion of the diagram below.  The asexual spores (conidia) are released into the environment in a process called germination.  Most often this occurs via the wind; however, other germinating helpers may include animals or water.  After germination, the dispersed haploid spores reform into conidia through mitosis and continue the cycle.  A single asexual spore is called a conidium and is also referred to as a mitospore.

                               

Below is an example of the asexual conidia. The name comes from the Greek word for dust, “konis”.  The conidophore is the structure which holds the dust like spores.  It is also one of the defining characteristics of P. chrysogenum because it resembles the shape of a paint brush.  The Greek word “Penicillius” literally means paintbrush. 

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