Functional analysis of beet necrotic yellow vein virus (BNYVV) RNA4 in fungal transmission.

Offers a functional analysis of beet necrotic yellow vein virus (BNYVV) RNA4 in fungal transmission. Insertion of full-length RNA4 of BNYVV and its mutants into a transcription plasmid; Coinoculation of the plasmid transcripts and RNAs extracted from a BNYVV isolate to Tetragona expansa; Inoculation of the recombinant isolates to sugar beet plants grown in a sand culture system containing Polymyxa betae; Finding that the efficiency of BNYVV transmission decreased with different deletions in the coding region of RNA4 and not affected by the frame-shift mutant with four nucleotides; Conclusion that some of the RNA4 sequence in the deleted region of nucleotide acids are needed to transmit the virus by fungus.