Rhizopus is a genus of common saprophytic fungi on plants and specialized parasites on animals. They are found on a wide variety of organic substrates, including "mature fruits and vegetables", jellies, syrups, leather, bread, peanuts and tobacco. Some Rhizopus species are opportunistic agents of human zygomycosis (fungal infection) and can be fatal. Rhizopus infections may also be a complication of diabetic ketoacidosis. This widespread genus includes at least eight species.
Rhizopus 400x magnification
Rhizopus species grow as filamentous, branching hyphae that generally lack cross-walls (i.e., they are coenocytic). They reproduce by forming asexual and sexual spores. In asexual reproduction, sporangiospores are produced inside a spherical structure, the sporangium. Sporangia are supported by a large apophysatecolumella atop a long stalk, the sporangiophore. Sporangiophores arise among distinctive, root-like rhizoids. In sexual reproduction, a dark zygospore is produced at the point where two compatible mycelia fuse. Upon germination, a zygospore produces colonies that are genetically different from either parent.
^Kirk PM, Cannon PF, Minter DW, Stalpers JA. (2008). Dictionary of the Fungi (10th ed.). Wallingford, UK: CABI. p. 599. ISBN978-0-85199-826-8.
^Chinn RY, Diamond RD. (1982). "Generation of chemotactic factors by Rhizopus oryzae in the presence and absence of serum: relationship to hyphal damage mediated by human neutrophils and effects of hyperglycemia and ketoacidosis". Infection and Immunity38 (3): 1123–29.
^Zheng RY, Chen GQ, Huang H, Liu XY. (2007). "A monograph of Rhizopus". Sydowia59 (2): 273–372.