sporangiophore

A sporangiophore is the stalk that bears a sporangium in certain fungi and oomycetes. It is typically an aerial or subaerial hyphal structure that rises from the vegetative mycelium and terminates in one or more sporangia, which contain the asexual spores known as sporangiospores. In many species, especially those in the Zygomycota (such as Rhizopus and Mucor), sporangiophores are coenocytic (lacking septa), though septate sporangiophores can occur in some taxa. Sporangia at the tip of the sporangiophore develop spores by mitosis and, upon maturity, release them to the environment, facilitating rapid dispersal.

Function and development: The sporangiophore elevates the sporangium to improve spore dispersal by air currents and can help protect the developing spores within the sporangial wall. Development begins from the vegetative mycelium, with the sporangiophore differentiating as a specialized hyphal segment that ends in the sporangium. After spore release, the sporangiophore may wither or continue to contribute to the fruiting body, depending on the species and environmental conditions.

Distinctions: Sporangiophores differ from conidiophores, which bear conidia externally without a surrounding sporangial sac. In addition to fungi, some oomycetes also produce sporangiophores that culminate in sporangia, illustrating the broader use of the term across related groups.

Examples: In Rhizopus and Mucor species, sporangiophores with terminal sporangia are characteristic features of their asexual reproduction. In Phytophthora and other oomycetes, sporangiophores similarly bear sporangia containing motile or nonmotile spores.