Caracterização da qualidade e técnicas de detecção de bactérias em sementes de arroz

Abstract

Taking into account the importance of rice, both in social and economic relevance that the pathogens are in the process of crop development objectives of this study was to characterize the physical, physiological and health of rice seeds, coming from the states of Rio Grande do Sul, Santa Catarina, Goiás, Roraima and verify the influence of different levels of contamination by bacteria and fungi on physiological quality of rice seeds, to test the pathogenic potential of isolates with different cultivars of which were derived; test different techniques for the isolation and growth of bacteria in the laboratory. To evaluate seed quality, tests were conducted moisture content, germination, first germination test, cold test, health testing (Blotter Test) beyond the test pathogenic bacteria were removed from their own seeds analyzed in the Blotter Test . For the evaluation of techniques for isolation and growth of bacteria we used the combined washed method of extraction with the PSA and Wakimoto culture media crushed method of extraction with PSA and Wakimoto culture media, evaluated the day 24, 48 and 72 hours of incubation with respect to number and size of bacterial colonies. In general, the samples have low vigor, good germination, low incidence of fungi and, when analyzed according to their state of origin, follow the standard set analyzed. The pathogenicity test showed no pathogenic bacteria tested as the rice seedlings were inoculated. The culture medium PSA is best used for the evaluation of colony size and number over time, the incubation period of 48 hours has become more favorable assessment of culture media on the number of colonies. The number of bacteria tends to stabilize and then decrease over time. The extraction method ground tends to be more efficient when they are evaluated over a sample of seeds. The characteristics of the seed samples influence the results, regardless of extraction method and the culture medium used.