NAMULONGE, Uganda — Before rows of tall, green bushes, Jude Aleu picks a cassava tuber off the ground and cracks it in half.
That shouldn’t be so easy. Healthy cassava tubers — a staple food crop in the region — can grow as thick as your upper arm. But the root in Aleu’s hands is stunted and gnarled because of a plant virus called brown streak disease. When he breaks it open, the flesh is streaked with brown and yellow, a necrosis that will render the harvest inedible.
“It’s corky,” said Aleu, a cassava safety manager for Uganda’s National Crops Resources Research Institute. “This root you cannot eat. Even animals cannot eat it.”