Abstract

ROCHA, Kelly Cristina Gonçales et al. Occurrence and genetic variability of Tomato severe rugose virus in pepper and tomato plants in São Paulo State. Summa phytopathol. [online]. 2010, vol.36, n.3, pp. 222-227. ISSN 0100-5405.  http://dx.doi.org/10.1590/S0100-54052010000300006.

From January/2007 to July/2008 a survey was carried out to evaluate the occurrence of begomoviruses in pepper and tomato crops from São Paulo State. Total DNA was extracted from 710 pepper and 103 tomato samples, and the presence of begomoviruses was tested by Polymerase chain reaction (PCR). The same samples were tested by Rolling Circle Amplification (RCA) followed by PCR, and some positive samples analyzed by RCA-RFLP and cleaved by the restriction enzyme HpaII to evaluate the genetic variability of these isolates. By PCR, 99 (13.94%) samples collected from pepper and 39 (37.86%) from tomato were positives for the presence of begomovirus, while by RCA-PCR 333 (46.90%) and 82 (79.61%) from pepper and tomato, respectively, indicating higher sensitivity of this technique. The 5' region of the coat protein (CP) gene and a segment of the intergenic region was analyzed indicating the presence of Tomato severe rugose virus (ToSRV) in pepper and tomato plants. However, the partial sequencing of clones from RCA products from a tomato sample indicated mixed infection of ToSRV with Tomato yellow vein streak virus (ToYVSV). By RCA-RFLP four restriction profiles were observed for ToSRV in pepper, while 18 profiles for begomovirus from tomato plants, indicating higher degree of genetic variability for begomovirus found in tomato plants compared to that in pepper plants.

Keywords : Geminiviridae; Bemisia tabaci; Field Survey; Solanum and Capsicum.