▁transport ▁mechanism ▁is ▁dependent ▁of ▁the ▁production ▁of ▁str ig ol act ones , ▁which ▁can ▁easily ▁travel ▁from ▁the ▁site ▁of ▁production ▁( ro ots ) ▁to ▁the ▁terminal ▁bud s ▁of ▁the ▁stem ▁through ▁the ▁x yle m . ▁ ▁E col ogy ▁ ▁Plant - f ung i ▁interaction ▁▁▁▁▁ ▁Str ig ol act ones ▁play ▁a ▁fundamental ▁role ▁in ▁plant - f ung i ▁interaction . ▁One ▁of ▁the ▁first ▁studies ▁made ▁in ▁Lot us ▁jap onic us ▁had ▁already ▁demonstrated ▁that ▁comp ounds ▁extracted ▁from ▁the ▁root ▁were ▁necessary ▁for ▁the ▁development ▁of ▁ar bus cular ▁my cor rh iz al ▁fung i ▁that ▁will ▁establish ▁a ▁sym bi otic ▁relationship ▁with ▁the ▁plant ' s ▁root . ▁These ▁same ▁find ings ▁were ▁true ▁for ▁different ▁plants ▁such ▁as ▁ma ize ▁and ▁s org hum . ▁Later ▁on , ▁the ▁comp ounds ▁responsible ▁for ▁the ▁branch ing ▁of ▁the ▁ar bus cular ▁fung i ▁were ▁isolated , ▁and ▁they ▁include ▁ 5 - de ox y str ig ol , ▁str ig ol ▁and ▁s org ol act one , ▁all ▁of ▁them ▁belonging ▁to ▁the ▁str ig ol act one ▁family ▁of ▁comp ounds . ▁The ▁process ▁of ▁branch ing ▁is ▁cru cial ▁to ▁establish ▁the ▁sym b ios is . ▁Since ▁this ▁branch ing ▁only ▁occurs ▁after ▁the ▁germ ination ▁of ▁the ▁sp ores ▁and ▁the ▁initial ▁growth ▁of ▁the ▁hy pha , ▁the ▁str ig ol act ones ▁required ▁for ▁germ ination ▁have ▁to ▁be