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Agro@mbiente On-line 2012
Incidence of seedborne fungi on pink trumpet tree (Tabebuia impetiginosa) and yellow poui (Tabebuia ochracea) in Roraima = Incidência de fungos associados a sementes de ipê-rosa (Tabebuia impetiginosa) e ipê-amarelo (Tabebuia ochracea) em RoraimaKeywords: Aspergillus , Curvularia , Fusarium , Seed pathology. = Aspergillus , Curvularia , Fusarium , Patologia de sementes. Abstract: The objective of this study was to identify and quantify fungi associated with seeds ipe-pink (Tabebuia impetiginosa), yellow-ipe (Tabebuia ochracea) and evaluate the effects of aseptic seed germination and seed seeding. The experiment was done at the Laboratory of Plant Science Center of Agrarian Sciences, Federal University of Roraima. Samples of ipê yellow and pink ipe were collected and extracted from fruits harvested in the urban area of the city of Boa Vista - RR. Each sample was divided into two sub-samples, treated and untreated, and were then submitted to germination and health analyses. The filter paper method was used for the health test where contaminated seeds were analyzed for the detection and identification of fungi. For the germination test method was also the filter paper, obtained the germination rate, rate of plants with lesions, number of seeds germinated and the rate of non-germinated seeds that had fungus. The results were subjected to variance analysis and when significant, means were compared by the Tukey test at 5% probability. The experimental design was completely randomized with four replications of 50 seeds for each treatment. Asepsis with 70% alcohol for a minute then with sodium hypochlorite (NaClO) to 2% for three minutes was positive for the elimination of fungi on seeds of ipe-yellow and ipe-pink, it favored germination and decreases the rate of seedlings with lesions. = Objetivou-se com o presente trabalho identificar e quantificar os fungos associados às sementes de ipê-rosa (Tabebuia impetiginosa), ipê-amarelo (Tabebuia ochracea) e avaliar o efeito da assepsia das sementes na germina o e na plantula. O Experimento foi realizado no Laboratório de Fitotecnia do Centro de Ciências Agrárias da Universidade Federal de Roraima. Foram coletadas amostras de sementes de ipê-amarelo e ipê-rosa extraídas de frutos colhidos na área urbana do Município de Boa Vista - RR. Cada amostragem foi dividida em duas sub-amostras, tratada e n o tratada, as quais foram submetidas aos testes de germina o e sanidade. O método utilizado para o teste de sanidade foi o papel de filtro, sendo as sementes contaminadas analisadas para a detec o e identifica o dos fungos associados às mesmas. Para o teste de germina o o método também foi o papel de filtro, obteve-se o percentual de germina o, percentual de plantulas com les es, número de sementes n o germinadas e percentual de sementes n o germinadas que apresentaram fungos. Os resultados foram submetidos a análise de variancia e, quando significativa, as médias foram comparadas pelo teste de
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