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Sugarcane yellow leaf virus (SCYLV; genus Polerovirus,family Luteoviridae) is a recombinant virus associated with yellow leaf disease,a serious threat to sugarcane in China and worldwide.Among the nine known SCYLV genotypes existing worldwide,COL,HAW,REU,IND,CHNI,CHN2,BRA,CUB and PER.the last five have been reported in China.In this study,the complete genome sequences (5,880 nt) of GZ-G218 and HN-CP502 isolates from the Chinese provinces of Guizhou and Ha inan,respectively,were cloned,sequenced and character ized.Phylogenetic analysis showed that,among 29 SCYLV isolates described worldwide.the two Chinese isolates clustered together into an independent clade based on the near-complete genome nucleotide (ORFO-ORF5) or amino acid sequences of individual genes,except for the MP protein (ORF4).We propose that the two isolates represent a novel genotype,CHN3,diverging from other genotypes by l.7-13.6% nucleotide differences in ORFO-ORF5,and 2.7-28.1 %,1.8-20.4 %,0.5-5.1 % and 2.7-15.9 % amino acid differences in PO (ORFO),RdRp (RNA-dependent RNA polymerase) (ORFl+2),CP (coat protein) (ORF3) and RT (readthrough protein) (ORF3+5),respectively.CHN3 was closely related to the BRA,HAW and PER genotypes,differing by l.7-3.8 % in the near-complete genome nucleotide sequence.Recombination analysis fur ther identified CHN3 as a new recombinant strain,arising from the major parent CHN-HNI and the minor parent CHN-GD-WY19.Recombination breakpoints were dis tributed mostly within the RdRp region in CHN3 and the four significant recombinant genotypes,IND,REU,CUB and BRA.Recombination is considered to contribute sig nificantly to the evolution and emergence of such new SCYLV variants.