The Collaborative International Dictionary of English v.0.48:

Sporangiophore \Spo*ran"gi*o*phore\
   (sp[-o]*r[a^]n"j[i^]*[-o]*f[=o]r), n. [Sporangium + Gr.
   fe`rein to bear.] (Bot.)
   The axis or receptacle in certain ferns (as Trichomanes),
   which bears the sporangia.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sporangiophore
    n 1: stalk bearing one or more sporangia