Molecular characterization of Rice black-streaked dwarf virus isolates causing maize rough dwarf disease in Shandong.
Four isolates of Rice black-streaked dwarf virus (RBSDV) were collected from the maize plants showing rough dwarf symptom in Linyi and Tai'an, Shandong province, China. The S10 genomic sequences of these isolates were determined and compared with those of 14 other RBSDV isolates. All of the four sequences were 1801 base pairs (bp) long including the 5′-UTR of 21 bp and the 3′-UTR of 103 bp. They all contained an open reading frame of 1677 bp (22-1698), encoding the coat protein (CP) of 558 amino acids. The sequences of these four RBSDV isolates and those of the major cp gene of 14 other isolates available in the GenBank were divided into two groups in the phylogenetic tree. Recombination analysis indicated that the isolate Lym2 was likely a recombinant of isolates Lym1 and Zhjs.