Abstract
HISTOPATHOLOGICAL and cytopahological studies on infected Hyocyamus muticus L. plants with a new potyvirus-Egyptian isolate with accession number KM497011 was investigated. The infected Hyocyamus muticus L. showing virus-like symptoms on its leaves in the form of a net mosaic, blistering, rugosity and malformation. Histopathology of an Egyptian potyvirus isolate-infected Hyocyamus muticus L. leaves using light microscopy showed abnormal structures of the lamina, epidermal cells, mesophyll tissue and vascular bundles compared with healthy one. Cy top athology of an Egyptian poty virus isolate-infected Hyocyamus muticus L. leaves using electron microscopy showed pinwheel and scrolls inclusion bodies and abnormal cell wall thickness, nucleus, chlorop last and no clear internal structure of mitochondria compared with healthy one. Our conclusion, the new Egyptian potyvirus isolate caused changes in the cells and tissue structure of henbane leaves as the same of other known potyvirus strains.