When you move apps to an SD card, it leaves a portion of the app on the phone. Android uses that portion of the app on the phone to know what the apps are and how to run them. When you rooted the phone, you basically lost the apps, so you will need to download them again.
It's not hard to download them, when you go into Google Play Store, select "My Apps" and at the top you will notice it says "Installed" and to the side it says "All". Swipe the screen over to "All" and it will show all the apps you have downloaded previously.
You also might want to reformat the SD card to reclaim the space used by the old apps -- or at least delete the old apps from the SD card.