Arcane demage and ascendent


I have one question. When I equip ascendent item, but I dont make any arcane demage is lower resist applied? When I have wraith on amulet, enemies become violet. But without are not violet. Thanks for reply.

U have to do arcane dmg on enemys to apply the resistance reduction to other elements, wrath talent helps with that because it makes arcane dmg on all around xD