Velgor

Velgors were natives of the planet Velgris, a vegetated world with a 40% covering of fruit trees. The Velgors' weekly chanting helped the fruit trees to ripen and the trees bore a different fruit each week. An attempt to mutate the fruit into an invading force by an unknown power (by using remote control to distort the chanting), was defeated by the Eleventh Doctor. (DWA: Harvest of Doom)