Yellow vein mosaic disease of pumpkin in Kerala

Abstract

Yellow vein mosaic disease of pumpkin ( Cucurbita moschata Dutch. ex Poir) caused by a virus, was investigated which was prevalent in Vellayanl and nearby localities. The symptoms appeared as faint yellowing of finer veins which later on develop into characteristic vein yellowing. In advanced stages of infection, chlorotic areas were seen on the leaf lamina along with vein yellowing symptoms. The size of the leaves was reduced markedly.The growth of infected plants was severely retarded. The infected plants produced less female flowers and when Infected at a later stage produced undersized fruits. Histopathological studies showed a reduction in thickness of the chlorotic portions of the infected leaves and the palisade cells were shortened and loosely packed. The mesophyll cells contained only few chloroplasts. The virus was not sap transnissible. But it could be transnitted through grafting* The virus was hot found to be transmitted through seeds.