VIEW ARTICLE

Vector Relations

Transcellular Transport of Barley Yellow Dwarf Virus Into the Hemocoel of the Aphid Vector, Rhopalosiphum padi. F. E. Gildow, Assistant professor, Department of Plant Pathology, Pennsylvania State University, University Park 16802; Phytopathology 75:292-297. Accepted for publication 25 September 1984. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/Phyto-75-292.

The ultrastructure of Rhopalosiphum padi reared on healthy oats or oats infected with the RPV isolate of barley yellow dwarf virus (BYDV) was studied to determine the site and cellular mechanisms involved in BYDV transport from the gut lumen into the hemocoel of aphid vectors. Virus particles were consistently associated only with cell membranes of the hindgut in 37 of 40 R. padi reared on RPV-infected oats. Virions were not associated with membranes of the stomach or intestinal regions of the midgut. Virions were not observed in midgut or hindgut of 19 aphids reared on healthy oats. The observed virions were immunologically labeled in vivo and identified as RPV. The mechanism for BYDV uptake into hindgut cells by endocytosis was supported by observation of virions adsorbed to the hindgut apical plasmalemma, in coated pits and in coated vesicles. Virions were observed to accumulate in tubular vesicles and lysosomes. Release of the virus into the hemocoel by fusion of virus-containing tubular vesicles with the basal plasmalemma was indicated. A site of luteovirus ingress into the vector at the hindgut is demonstrated. This specific site could be involved in regulating virus uptake.