The 20-year-old Surrey rising star is a direct replacement for Middlesex left-hander Dawid Malan.
Ollie Pope replaced Dawid Malan in the England team for the 2nd Test vs India.
Chris Woakes replaces fellow all-rounder Ben Stokes, who faces a court hearing this coming week in Bristol.
India vs England, 1st T20I: Dawid Malan has played five T20Is for England.
Root was out to a superb diving catch by Mitchell Marsh at square leg for 83 in the day's penultimate over