DIFICULDADES E LIMITACÕES EM TESTE SOROLÓGICO E MOLECULAR UTILIZADOS PARA DIAGNOSE VIRAL EM Solanum lycopersicon

Abstract

The tomato crop stands out as one of the most productive nightshades both in Brazil and in the world. Its importance is related to both nutritional and socioeconomic issues. However, several problems can cause severe losses in the productivity of such culture, highlighting the susceptibility to viral infections, usually transmitted by vector insects. Our objective was to carry out diagnosis of phytopathogenic virus genera in symptomatic tomato samples present in a tomato-producing area in Núcleo Rural Taquara, Planaltina DF, using serological (Dot-ELISA) and Molecular (RT PCR) tests. Also, report on the difficulties and limitations encountered during the research Tomato foliar samples symptomatic for phytoviruses were collected in a rural producer's area in the rural Nucleus Taquara DF. In total, Thirty-six samples were taken to the Laboratory of Plant Virology in order to carry out viral diagnostic tests. The first test performed was the Dot-ELISA serological test, in which specific antibodies PVY and PEPMV were used for detection of Potyvirus and GRSV TCSV, TSWV for detection of Orthotospovirus. Of the thirty-six samples, only seven reacted to the antibodies used in the detection of Potyvirus. In relation to the antibodies used for the detection of Orthotospovirus, only four samples reacted, thus being positive. Viral RNA from all samples that tested positive in the serological test was extracted by the TRizol® method in order to carry out molecular detection. Then, a Reverse Transcription was performed in order to produce complementary DNA, followed by an RT-PCR using specific primers, to detect Potyvirus and Orthotospovirus. The result of the molecular test was not what was expected, as we observed the absence of bands in the gels, and no amplification of the PCR product. Thus, it was necessary to carry out a new test, with other samples, for comparison purposes. Thus, our work shows that both detection tests have some limitations, requiring essential care so that we can obtain effective results.