摘要

A new tospovirus, HCRV 2007-ZDH, was isolated from a Hippeastrum sp. plant displaying necrotic and chlorotic ringspot symptoms in Yunnan province. This virus isolate was characterized based on particle morphology and RNA sequences analyses. Quasi-spherical, enveloped particles measuring about 70-100 nm, typical of tospoviruses, were observed in sap and cells of the infected plants. Transmission studies by inoculating this isolate mechanically to Hippeastrum sp. confirmed that 2007-ZDH is the causal agent of the chlorotic ringspot disease of Hippeastrum sp. The complete sequence of S RNA of 2007-ZDH was 2,744 nucleotides in length, sharing 74.4 % nucleotide identity with Tomato yellow ring virus (TYRV) isolate tomato (AY686718). The S RNA encoded a non-structural protein (NSs) (444 aa, 50.4 kDa) and the nucleocapsid (N) protein (273 aa, 30.1 kDa).The deduced NSs protein shared amino acid identities of 78.6, 76.3, and 74.9 % with that of TYRV, IYSV, and PolRSV, respectively. The deduced N protein shared amino acid identities of 86.1, 84.7, and 70.0 % with that of PolRSV, TYRV, and IYSV, respectively. These results suggest that the chlorotic ringspot virus belongs to a new tospovirus species, for which the name Hippeastrum chlorotic ringspot virus (HCRV) is proposed.

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