Taking forward the agenda of NDTV-Dettol Banega Swachh India 12-hour cleanathon, Campaign ambassador Amitabh Bachchan starts 'Plant A Tree Challenge'. He not only challenges everyone to plant a tree, but to personalise it and nurture it like their own child. He says, "Plant a tree, take a video of it, send it to me and I'll share it on social media."