Author(s)

Xiaoya Jing, Liuqing Sun, Wei Chen

Corresponding Author

Xiaoya Jing

Abstract

Sugarcane mosaic virus (SCMV) is a great threat to the yield of sugarcane and maize. It is necessary to understand the evolutionary mechanism of SCMV. The study aimed to reveal the effect of host on evolution of SCMV. The leaf samples of maize with typical symptom were collected from Shanxi province and tested by DAS-ELISA and RT-PCR. Compared with online databases, one new SCMV isolate was found and further studied. The complete genome of the isolate is 9594 nt long, and it encodes a 3064 amino acid poly-protein. It was pairwise compared and phylogenetic analyzed with 20 SCMV isolates from genebank. The results showed that the 21 isolates could be divided into two divergent evolutionary groups (Group I and II) based on the complete genome, which was associated with the host species. Each gene of the 21 isolates were also conducted with pairwise comparison and phylogenetic analysis, similar results were obtained for six genes (6K2, CP, HC-Pro, NIa-Vpg, P1 and P3), among which six amino acid (AGGVFI) of 6k2 from 27 to 32 sites seemed to be conservative among SCMV sugarcane isolates, while SAGVFT were conservative among SCMV maize isolates. The results confirmed that the host produced the selection pressure on the evolution of SCMV, and the six amino acid in 6K2 may respond to this selection. The finding might be helpful for understand the host effect on the evolution of SCMV. In addition, it may be useful for the design of long-term and sustainable management strategies for controlling SCMV.

Keywords

SCMV, selection pressure, host, amino acid