diff --git a/inc/field/dropdownfield.class.php b/inc/field/dropdownfield.class.php
index e6802a297..fa56a1f1d 100644
--- a/inc/field/dropdownfield.class.php
+++ b/inc/field/dropdownfield.class.php
@@ -331,7 +331,7 @@ public function buildParams($rand = null) {
       if (isset($decodedValues['show_tree_depth'])
          && $decodedValues['show_tree_depth'] > 0
       ) {
-         $dparams_cond_crit['level'] = ['<=', $decodedValues['show_tree_depth'] + $baseLevel];
+         $dparams_cond_crit[$itemtype::getTableField('level')] = ['<=', $decodedValues['show_tree_depth'] + $baseLevel];
       }
 
       $dparams['condition'] = $dparams_cond_crit;