Purple-top wilt, a disease of potato caused by tomato big-bud virus.

Abstract

The symptoms of purple-top wilt on potato are described and illustrated and data on the tuber transmission of the virus are presented. The disease is caused by the tomato big-bud virus, although the symptoms differ markedly from those usually produced by this virus. Economic loss results both from the direct effect of current-season infection and from missing hills in the subsequent crop caused by the failure of affected tubers to sprout.