Neutralization of Beet Western Yellows Virus by Antisera Against Barley Yellow Dwarf Virus

Abstract

A possible relationship between beet western yellow virus (BWYV), a damaging virus of dicotyledonous plants, and barley yellow dwarf virus (BYDV), a virus of major economic importance in monocotyledonous grains and grasses, was suspected based on their biological properties. Antisera prepared against the MAV, RPV and PAV isolates of BYDV in New York [USA] were tested against 4 isolates (ST-1, ST-7, ST-9 and E-4) of BWYV in California [USA]. Virus-antiserum mixtures were subjected to density-gradient centrifugation, analyzed photometrically and tested for virus neutralization. Antisera prepared against the 3 isolates of BYDV reduced or eliminated virus antigen in scanning patterns and reduced or eliminated virus in the normal BWYV-bearing zones. Antiserum against healthy shepherd''s purse [Capsella bursa-pastoris] or oat [Avena byzantina] juice did not affect scanning patterns of infectivity. In contrast to the reaction of BYDV antiserum, none of 29 different antisera to 23 different viruses neutralized BWYV. In 5 of 14 tests Myzus persicae transmitted BWYV to oats. In 9 of 20 tests Macrosiphum avenae transmitted BWYV to shepherd''s purse. Inoculations of over 850 BWYV host plants failed to establish that the PAV, RPV, or MAV isolates of BYDV could infect them.