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Defined literally, an endophyte is an organism which lives inside a plant (ie," endo" is derived from the Greek word" endon" meaning within, and" phyte" is derived from the Greek word" phyton" meaning plant). However, the term" endophyte" has evolved microorganism-specific connotations, referring to fungi which invade the stems and leaves of plants but cause no symptoms of disease (Carroll 1988; Clay 1988; Isaac 1992; Wilson 1993; Wennstrom 1994). Some of these fungi are considered to be mutualistic, because they afford host plants a degree of protection from herbivory. In addition, the term endophyte has been used to describe mycorrhizal fungi (eg, O'Dell and Trappe 1992), but because their characteristic external hyphae emanate into the soil surrounding infected root tips, such fungi necessarily reside only partly inside plant tissues. In either case, it seems inappropriate to redefine the generic term" endophyte" so that it refers only to a specific group of microorganisms, be they completely endophytic stem and leaf fungi or the partly endophytic mycorrhizal fungi. If the type of fungi described by Carroll (1988), Clay (1988), Isaac (1992), and Wilson (1993) were a relatively homogeneous group and the only truly endophytic microorganisms, ie, residing entirely within plant tissues, there could be some justification for redefinition of this term with specific mycological connotations. However, they are not. The relatedness of this group of fungi has been questioned (Wennstrom 1994), and they are most certainly not the only type (s) of microorganisms which live inside plant tissues. Recognizing this problem, Wilson (1995) recently proposed to …