Tomato rugose mosaic virus in Tomato Crops in São Paulo State, Brazil

Geminiviruses were of limited economic importance to tomato crops until the introduction of biotype B, when an increase in the incidence of begomovirus was reported (Ribeiro ., Arch. Virol. 148:281. 2003). In recent years, the occurrence of geminivirus in tomato causing a severe outbreak has been observed in the Campinas region, SP. In preliminary surveys (ToYVSV) turned out to be the most frequent begomovirus species, affecting about 70% of tomato crops. Occasionally, however, another possible begomovirus, inducing leaf crumple, has been noticed affecting tomato in that region (Colariccio ., Summa Phytopathol. 27:105. 2001). The present work aimed to identify the virus associated with the leaf crumple symptom. Thus, leaf samples from affected ‘Carmen’ tomato plants from Mogi Guacu, SP, showing growth reduction, green and yellow mosaic, besides leaf crumple and curling, were submitted to electron microscopy, mechanical, graft and transmissions, as well as DNA extraction for PCR using universal primers (Rojas ., Plant Dis. 77:340. 1993). Sequencing and phylogenetic analysis were performed to compare this virus with other geminivirus sequences deposited in the GenBank. Typical geminated particles were observed in negatively stained preparations from foliar veins. observation revealed the presence of hexagonally-packed crystalline array or of loose aggregates in the nuclei of phloem-infected parenchyma cells, with partial alteration of nucleoli into a granular structure. These cytopathic effects corresponded to those described for begomoviruses. The virus was transmitted by and graft, but not mechanically, like (ToRMV) from Minas Gerais State. A DNA-A fragment of about 1.2 kbp