A heavy sprayer strapped to the back. Hours of trudging along narrow paddy ridges. Droplets of pesticide drifting onto skin and into lungs. For generations, this has been the unchanging portrait of the Bangladeshi farmer. That portrait may finally be about to change. Recently, in a field in Pangsha, Rajbari, more than a hundred farmers stood watching something they had never seen before. A state-of-the-art drone hummed overhead