Quantificação e caracterização morfológica e molecular de populações de meloidogyne spp. de regiões produtoras de soja de Brasil

• Autor(a) principal: Oliveira, Camilla Martins de
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000007ww8
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/5957
• topic: Nematoide-das-galhas; Monitoramento; Diagnóstico; Glycine max; Esterase; qPCR; Root-knot nematode; Monitoring; Diagnosis; Glycine max; Esterase; AGRONOMIA::FITOSSANIDADE

Nematodes cause losses in plants throughout the world that can be translated into many economic losses. The root-knot nematodes (Meloidogyne sp.) are the most common and destructive pathogens within this group. In order to get an efficient method of nematode management, it is need to identify species and quantify accurately and reliably. The aim of this research was to optimize an assay based on real-time PCR to detect and quantify M. incognita. For this purpose the effectiveness of different DNA methods of extraction were compared through the values of Ct intervals. The DNA extraction was made from 100 individual nematodes by the methods: CTAB, Phenol: Chloroform and commercial kit (PureLink® Genomic ADN Kit, Invitrogen). In the comparative analysis using the three methods the CTAB method and commercial kit obtained similar Ct values. The CTAB was the best method of extraction with less variation among the replications and showed higher linearity of the standard curve in comparison with the other methods tested. It was possible to quantify nematodes in the samples based on the intervals of the Ct values established from different numbers of nematodes (1, 10, 25, 100, 250, 500 and 750). This study demonstrated that qPCR technique is a sensitive and reliable alternative for the quantification of M. incognita that may help laboratories of diagnose and field survey. Twenty-six populations of the root-knot nematode (Meloidogyne spp.) from five locations of the state of Bahia, five from the state of Mato Grosso, four from the state of Goiás and one from the state of Minas Gerais, were characterized based on morphology of perineal cut, biochemical analysis through esterase profile and molecular analysis with specific primers. Identification of nematodes in the samples using the analysis of perineal cut, esterase profile and molecular analysis was possible, but with some variations in the perineal patterns and some atypical profiles of esterase. In the analyses of esterase profiles were found 69.23% of M. javanica with esterase profiles J3 and J2, and 30.77% of M. incognita with esterase profile I1. There was a higher occurrence of M. javanica in the areas cultivated with soybeans. Molecular analysis showed to be practical and accurate.