Dormancy breaking in Mauritia flexuosa seeds by using mechanical scarification and soaking = Supera o de dormência em sementes de buriti por meio da escarifica o mecanica e embebi o

The majority of Arecaceae species presents difficulties to germinate, even under appropriate conditions, complicating the seedlings production process. This study aimed at evaluating the influence of seed scarification and soaking in the emergence and development of Mauritia flexuosa seedlings. The treatments consisted of a combination of seed soaking and scarification methods, in a completely randomized design, in a 2 x 3 + 1 factorial scheme, with five replications. Seeds with and without scarification, combined with soaking methods (not soaked seeds and seeds soaked for 30 days, with and without daily water renewal), plus an additional treatment, where the seeds were scarified after soaking for 30 days, were tested. The seedlingemergence up to 146 days after sowing (d.a.s.) was evaluated, as well as the emergence rate index (46 and 146 d.a.s.) and growth components (146 d.a.s.). The results were submitted to the variance analysis (F test) and means compared by using the Tukey test, at 5%. It was possible to conclude that the Mauritia flexuosa seeds presented tegument dormancy. The seed scarification increased the germination rate, however, it contributed to increase the seeds mortality rate. The soaking of nonscarified seeds for 30 days, with daily water renewal, improved the potential for seed germination. The mechanical scarification, without or after soaking the seeds in water, increased the Mauritia flexuosa seedlings mortality rate, and it is not, therefore, a suitable method for dormancy breaking. = A maioria das espécies de Arecaceae apresenta dificuldades para germinar, mesmo sob condi es adequadas, dificultando a produ o de mudas. Objetivou-se, com este trabalho, avaliar a influência da escarifica o e embebi o de sementes na emergência e desenvolvimento de mudas de buritizeiro. Os tratamentos foram compostos pela combina o de métodos de embebi o e escarifica o de sementes, adotando-se o delineamento inteiramente casualizado, no esquema fatorial 2 x 3 + 1, com cinco repeti es. Foram testadas sementes com e sem escarifica o, combinadas com métodos de embebi o (sementes n o embebidas e sementes embebidas por 30 dias, com e sem renova o diária de água), além de um tratamento adicional, onde as sementes foram escarificadas após a embebi o por 30 dias. Foi avaliada a emergência de plantulas aos 46, 66, 86, 106, 126 e 146 dias após a semeadura (DAS), bem como o índice de velocidade de emergência (46 e 146 DAS) e os componentes de crescimento (146 DAS). Os resultados foram submetidos à análise de variancia (Teste F) e as médias comparada