This is a very interesting question, and may have many different answers. My first thought would be to assess whether your daughter's skills at repeating aloud what she is reading translate to total reading comprehension. Is she able to understand and process what she is reading, and to form new ideas and thoughts around it?
Another possible answer has to do with test anxiety. A lot of times, it's easy to do something, but hard to do it again in a testing environment. Does your daughter have enough time for the test, or does she feel rushed?
First off, I would recommend talking to the teacher and broaching your concerns with her. If your daughter is feeling anxious in a test environment, is there some way that she can approach tests in a more relaxing way? Test-taking is a skill that will be needed throughout your child's schooling, so it's a good idea to address this now. Same goes with your daughter's reading skills in general. Is she truly understanding what she reads? If the problem persists and you are at a loss, you may also want to contact a specialist to see if they have any insight.