Molecular Characterization of a Novel Monopartite Begomovirus Infecting Weeds and Important Crops in Yunnan, China.

The genus Begomovirus constitutes a group of devastating plant viruses causing significant economic losses in the production of agricultural crops. In the present study, conducted in Yunnan province, China, a novel monopartite begomovirus was identified from Bidens pilosa, Crassocephalum crepidioides, tomato, pepper, and common bean, showing severe disease symptoms. The complete genome of the virus shows the typical organization of monopartite begomoviruses and shares the highest nucleotide sequence identity (88.73-88.95%) with crassocephalum yellow vein virus (CraYVV). According to the species criteria of the genus Begomovirus, this virus is a novel Begomovirus species, which has since been named "bidens pilosa leaf crumple virus (BpLCrV)". Recombination analysis revealed that the novel species is a potential recombinant begomovirus derived from CraYVV and ageratum leaf curl virus (ALCuV), and phylogenetic analysis showed that BpLCrV was clustered with tomato yellow leaf curl Thailand virus (TYLCTHV) from China. We successfully developed a BpLCrV infectious clone. Agrobacterium-mediated inoculation of the BpLCrV infectious clone could effectively infect Nicotiana benthamiana, Nicotiana glutinosa, and Datura stramonium and cause disease symptoms. Thus, in this study, BpLCrV was, for the first time, identified and characterized as a novel begomovirus that infects not only weeds but also different important crops, potentially threatening agricultural production.