Fungus-to-be (5)
I believe the answer is:
spore
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">fungus-to-be</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for spore that I've seen before include "Asexual reproductive body" , "Ropes (anag.)" , "Fungus reproducer" , "Tiny reproductive cell of fungus or fern" , "Reproductive body produced by fungi" .)