VIEW ARTICLE

Ecology and Epidemiology

Relative Transmissibility of Barley Yellow Dwarf Virus from Sources with Differing Virus Contents. Ana-Maria N. Pereira, Graduate assistant, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, Present address: Departamento de Proteccao de Plantas, Universidade de Tras-os-Montes e Alto Douro, 5000 Vila Real, Portugal; Richard M. Lister, Derek J. Barbara, and G. E. Shaner. Professor, visiting research plant pathologist, and professor, respectively, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907. Phytopathology 79:1353-1358. Accepted for publication 25 July 1989. Copyright 1989 The American Phytopathological Society. DOI: 10.1094/Phyto-79-1353.

Detached individual leaves of cereal plants with differing virus contents were compared as virus sources for the acquisition and transmission of three barley yellow dwarf virus (BYDV) isolates by specific (i.e., relatively efficient) or nonspecific (i.e., relatively inefficient) vectors. Overall, there was no convincing evidence of significant effects on virus transmission efficiency due to differences in virus content. However, in further experiments in which aphids fed on virus preparations through a Parafilm membrane, correlation between virus concentration and efficiency of acquisition and transmission was evident for both efficient and inefficient vectors. Aphids also acquired virus more efficiently when feeding on virus through a Parafilm membrane than when feeding on leaves containing a similar concentration of virus as assessed by ELISA of extracts. The combined results indicated that overall virus content may not the primary factor limiting the acquisition of BYDV from plants by vectors, and that its effects may be overshadowed by other factors, including uneven distribution of virus within the leaf.