As I posted in another thread, nobody publishes "Supports USB-OTG" in their spec sheets, and contrary to what the USB Organization web site says, not every phone offers this feature. To find out what you might not want to know, first determine whether your phone supports it.
Go to the Google Play store, search for "OTG Checker" and install your choice of the apps you'll find there. I've used one called OTG? (with the question mark). It will tell you immediately if your phone supports USB-OTG or not. If it doesn't, then you're out of luck. I don't think this is something that rooting will fix.