Companion plants affect colonization ofMyrica ceriferaby vesicularndash;arbuscular mycorrhizal fungi

摘要

The vesicularndash;arbuscular mycorrhizal (VAM) status ofMyrica ceriferaL. (wax myrtle) was investigated under greenhouse and field conditions.Myrica ceriferaandPaspalum notatumFluuml;gge (bahiagrass) were grown in inter- and intra-specific plant combinations with and without VAM fungi. Roots of field-collectedM.ceriferawere also examined for colonization by VAM fungi.Myrica ceriferabecame colonized by VAM fungi only in the presence of a VAM colonized grass plant; however, arbuscules were consistently lacking. VAM fungi had no effect on root or shoot growth ofM.cerifera. When grown in the presence ofP.notatum, shoot growth ofM.ceriferawas reduced, regardless of inoculation treatment. Colonization of field-collectedM.ceriferaroots ranged from 0 to 75; however, nearly all samples lacked arbuscules. Unexpectedly, samples from wet sites had the highest colonization levels. Failure ofM.ceriferato become colonized when grown without a VAM companion plant and the absence of arbuscules whenM.ceriferabecame colonized in the presence of a VAM companion plant suggest that the VAM association ofM.ceriferais nonfunctional.Key words: arbuscule,Glomus, interspecific, intraspecific, nonhost.