SCREENING FOR BARLEY YELLOW DWARF LUTEOVIRUS RESISTANCE IN BARLEY ON THE BASIS OF VIRUS MOVEMENT

The movement of barley yellow dwarf luteovirus (BYDV) was evaluated in susceptible and resistant barley and bread wheat genotypes. After lea f inoculation, the virus infected the root system and the growing poin t of susceptible earlier than resistant barley genotypes. No differenc e in virus movement occurred in resistant and susceptible wheat genoty pes. It was possible to reliably differentiate susceptible from resist ant genotypes when root extracts of 41 barley genotypes were tested by DAS-ELISA 3 or 4 days after inoculation at the oneleaf stage. When ba rley plants inoculated at the two- or three-leaf stage were assayed by tissue-blot ELISA on nitrocellulose membrane, virus was detected in t he phloem vessels of the growing points of the susceptible, but not of the resistant genotype, 4-6 days after inoculation. Our results thus suggest that screening for BYDV resistance in barley could be done qui ckly and cheaply especially when assays are made by the tissue-blot te st.