Soilmicrobesmaybecriticalplayersindeterminingtheallelopathicpotentialofsomeplants.LowlevelsofplantcommunitybiopersityinEucalyptusplantationshavebeenattributedtotheallelopathicpotentialofthesetreespecies.TheroleofsoilmicrobesintheallelopathiceffectofleafleachatesofthehybridtreeEucalyptusgrandis9E.urophylla,wastestedinPetridishassayswithBrassicachinensisasareceiverplant.Soilswerecollectedfromeitheralocalgarden(soilA)oraEucalyptusplantation(soilB)andhalfofeachsoilwassterilizedtoremovemicrobes.ThesesoilswerethentreatedwithE.grandis9E.urophyllaleachatesfor0-72h.SeedgerminationofB.chinensiswassignificantlyinhibitedinsoilstreatedwithleafleachatesrelativetountreatedsoils.Theinhibitoryeffectoftheleafleachateswasmorepronouncedinsterilizedsoils.Totalphenoliccontentwasobviouslowerinnonsterileleachatetreatedsoilsthaninsterilesoils.BiomassofB.chinensiswasnegativelycorrelatedwiththetotalphenoliccontentinsoils.OurfindingssuggestthatsoilmicrobescanalleviatetheallelopathicpotentialofEucalyptusandtherebyitsnegativeimpactonplantgrowth.
