Archivio Journal of Plant Pathology

Abstract:

Pepper (Capsicum annum L.), a member of the family Solanaceae, is native of South and Central America. In April 2015 mosaic and necrotic symptoms were observed on leaves and stems of pepper plants in the Imbabura province of Ecuador. Based on the type of symptoms, infection by a tospovirus was suspected. Symptomatic pepper samples were screened by TAS-ELISA using specific antibodies to Tomato spotted wilt virus (TSWV) (Agdia, USA), a member of the genus Tospovirus, family Bunyaviridae transmitted by thrips in a persistent and circulative manner. The presence of TSWV was ascertained by RT-PCR using total RNA isolated from ELISA-positive samples with the RNeasy Plant Mini kit (Qiagen, USA). DNA fragments of ca. 800 bp were amplified using degenerate universal tospovirus primers (Chu et al., 2001). A PCR product was custom-sequenced (Macrogen, South Korea) and the sequence was deposited in GenBank as accession No. KT590401. Sequence analysis (BioEdit v. 7.05) of the TSWV isolate from Ecuador with other TSWV isolates showed 97.3% and 95.3% maximum identity at the nucleotide and amino acid levels, respectively. A phylogenetic tree based on nucleotide sequences constructed using MEGA version 4.1 revealed a clustering of TSWV-Pepper from Ecuador with TSWV-Chrysanthemum from South Korea (KC261974), TSWV-Pepper from South Korea (HM581940), TSWV-Leonurus sibiricus from South Korea (KM076651) and TSWV-Tree tomato from Ecuador (KP772268). To the best of our knowledge this is the first report of the occurrence of TSWV on capsicum in Ecuador.