diff --git a/purchase_packaging/models/purchase_order_line.py b/purchase_packaging/models/purchase_order_line.py
index 626b0027e2bc..4444d4e83cae 100644
--- a/purchase_packaging/models/purchase_order_line.py
+++ b/purchase_packaging/models/purchase_order_line.py
@@ -15,7 +15,8 @@ def _default_product_purchase_uom_id(self):
     product_tmpl_id = fields.Many2one(
         related='product_id.product_tmpl_id',
         comodel_name='product.template',
-        readonly=True
+        readonly=True,
+        store=True,
     )
     packaging_id = fields.Many2one(
         'product.packaging',