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The complete genome of a novel bipartite begomovirus (genus Begomovirus, family Geminiviridae) was cloned from a severely diseased yellow Peruvian chili pepper ( Capsicum baccatum cv. Pendulum) plant collected in the department of La Libertad, Northern Peru and full-length sequenced. The two genomic components share a common region of 156 nucleotides with a 100% sequence identity. Analysis of the genome organisation and phylogenetic comparisons revealed that the virus is a typical New World begomovirus. The closest related begomovirus, an isolate of Tomato yellow vein streak virus ( ToYVSV), shared only 76.8% nucleotide sequence identity for the DNA-A component. Therefore, following species demarcation criteria of the International Committee on Taxonomy of Viruses, this virus isolate belongs to a new begomovirus species for which the name pepper leafroll virus ( PepLRV) is proposed. Pepper plants infected with the cloned PepLRV isolate developed leaf roll symptoms similar to those observed in field-infected plants suggesting this virus as the causal agent of the disease syndrome observed in the field. Widespread occurrence of PepLRV throughout Peru was demonstrated, infecting plants of diverse cultivated species such as tomato, pepper, common and pallar beans, and of the weed species Nicandra physaloides. Low genetic diversity was observed among PepLRV isolates present in this country with no evident geographical or temporal structure of the population, typical of a recent founder effect. This is the first report of a begomovirus infecting pepper and bean crops in Peru. [ABSTRACT FROM AUTHOR]

Abstract: The monopartite nature of the begomovirus tomato leaf deformation virus (ToLDeV) reported in Peru is demonstrated here. The DNA molecule cloned from an infected plant was shown to be fully infectious in tomatoes inducing leaf curling and stunted growth similar to that observed in field-infected plants. The viral DNA was reisolated from systemically infected tissues of inoculated plants, thus fulfilling Koch''s postulates. ToLDeV was demonstrated, therefore, as the causal agent of the disease syndrome widespread in tomato crops in Peru. This virus was shown to be present throughout the major tomato-growing regions of this country, both in tomatoes and wild plants. Analyses of the sequences of 51 ToLDeV isolates revealed a significant genetic diversity with three major genetic types co-circulating in the population. A geographical segregation was observed which should be taken into account for virus control. Constraints to genetic divergence found for the C4 gene of ToLDeV isolates suggest a relevant function for this protein. The results obtained confirm ToLDeV as a monopartite begomovirus native to the New World, which is a significant finding for this region. [Copyright &y& Elsevier]