Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: August 9, 1997
Publication Date: N/A
Collections of aphids migrating into winter wheat fields in 1994 revealed an abnormally high number of R. padi individuals transmitting BYDV-RMV. In other years BYDV-RMV was associated with R. maidis individuals and rarely with R. padi. Here we investigate the biological and molecular diversity of fRMV isolates and the diversity of R. padi populations in NY. All the RMV isolates obtained from R. padi in 1994 tested positive only for RMV by ELISA and all were efficiently transmitted by R. maidis in laboratory tests. Transmission efficiency by R. padi varied among the isolates and among the aphid clones. The coat protein (CP) gene of the NY-RMV type isolate and numerous RMV field isolates was amplified by reverse transcription-polymerase chain reaction and subsequently digested with Sau 3A and Hae III. Four unique RFLP patterns were identified and none of the field isolates were similar to the NY-RMV type isolate. The CP gene of the NY-RMV isolate, as well as, five of the field isolates were cloned and sequenced. Sequence analysis showed that the field isolates were more similar to RMV isolates from Illinois and Minnesota than to the NY-RMV type isolate.