Analysis and detection of coat protein gene of barley yellow mosaic virus and barley mild mosaic virus by RT-PCR.
Using reverse transcription polymerase chain reaction (RT-PCR), a rapid and sensitive assay for the detection and identification of barley yellow mosaic bymovirus (BaYMV) and barley mild mosaic bymovirus (BaMMV) was adapted. Two units of primers from each virus were selected and used for the determination of 2 different viruses. PCR fragments of BaYMV (approx. 0.9 kb) and BaMMV (approx. 0.8 kb) were obtained from the designed method for the assay of BaYMV and BaMMV coat protein. PT-PCR fragments were cloned using vector pT7 Blue and the sequences of the selected clones were analysed. Coat protein of BaYMV and that of BaMMV consisted of 297 amino acids (891 nucleotides) and 251 amino acids (753 nucleotides), respectively. The analysis of coat protein genes from these 2 viruses showed that 45.6% of nucleotide sequences and 34.9% of amino acids in BaYMV were homologous to those in BaMMV.