osph orus ▁is ▁obtained ▁by ▁the ▁my cor rh iz al ▁fung us ▁from ▁the ▁surrounding ▁soil ▁in ▁three ▁different ▁forms ; ▁organ ic ▁ph osph orus , ▁ph osph ate , ▁and ▁in organ ic ▁ph osph orus ▁comp ounds . ▁O ften ▁times ▁these ▁comp ounds ▁are ▁strongly ▁bound ▁to ▁c ations ▁and ▁need ▁to ▁be ▁pro ton ated ▁and , ▁or ▁cat abol ized ▁to ▁become ▁bio available . ▁My cor rh iz al ▁fung i ▁are ▁extremely ▁efficient ▁at ▁doing ▁this ▁due ▁to ▁their ▁extensive ▁soil ▁surface ▁area ▁as ▁well ▁as ▁high ▁en zym atic ▁divers ity . ▁Once ▁fre ed ▁from ▁the ▁soil ▁the ▁ph osph orus ▁comp ounds , ▁primarily ▁in organ ic ▁ph osph ate , ▁are ▁transferred ▁through ▁two ▁proposed ▁path ways . ▁The ▁first ▁involves ▁the ▁active ▁transport ▁of ▁in organ ic ▁ph osph orus , ▁primarily ▁as ▁ph osph ate ▁through ▁Pi ( in organ ic ▁ph osph orus ) ▁trans por ters ▁out ▁of ▁the ▁fung us ▁into ▁the ▁inter fa cial ▁ap op last , ▁where ▁it ▁is ▁pro ton ated ▁due ▁to ▁the ▁acid ic ▁nature ▁of ▁the ▁inter fa cial ▁ap op last ▁to ▁form ▁di h ydro gen ▁ph osph ate ▁and ▁then ▁subsequently ▁transferred ▁through ▁active ▁Pi ▁trans por ters ▁into ▁the ▁plant ▁cell . ▁The ▁second ▁method ▁re lies ▁on ▁pass ive ▁eff l ux ▁of ▁Pi ▁from ▁the ▁fung us ▁and ▁active ▁u pt ake ▁by ▁the ▁plant , ▁as ▁in ▁the ▁prior ▁path way