Resumo: O conhecimento das condições ótimas para a germinação, principalmente quanto à influência dos métodos de escarificações térmicas e mecânica, é de fundamental importância, tendo em vista que à recomendação destes métodos variam entre sementes de diferentes espécies. Assim, objetivou-se neste trabalho avaliar os métodos de escarificação em sementes de açaí com e sem refrigeração visando acelerar a emergência, o crescimento e desenvolvimento inicial de plântulas de açaizeiro. O delineamento experimental foi inteiramente casualizado, com cinco tratamentos e a parcela composta por 50 sementes com cinco repetições. No tratamento testemunha (T1) as sementes não foram escarificadas; (T2) escarificação térmica em água a 80ºC por duas horas; (T3) escarificação térmica em água a temperatura de 100ºC por duas horas; (T4) escarificação mecânica em lata de alumínio previamente perfurada com movimentos circulares por quatro minutos; (T5) imersão em 20 L de água contendo 500 g de soda cáustica, durante duas horas. Avaliou-se o número de plântulas emergidas (NPE, %), o comprimento da parte aérea das plântulas (CPA, cm), o comprimento da folha (CF, cm), o comprimento da raiz (CR, cm) e a massa seca (MS, g). O resfriamento prévio dos frutos de açaí não é indicado, pois reduz a percentagem de emergência das sementes e o desenvolvimento inicial das plântulas. Maior percentagem de emergência e desenvolvimento inicial de plântulas de açaí são obtidos com escarificação mecânica das sementes. Palavras-chave:Euterpe oleracea. Germinação. Dormência de sementes. Abstract:The knowledge of the optimum conditions for germination, mainly as to the influence of thermal and mechanical scarification methods is of outstanding importance, having in one's mind that the use of these methods range among seeds of different species. So, it was intended in this work to evaluate the scarification methods on açaí seeds with or without refrigeration aiming to accelerate emergence, growth and initial development of açaí palm seedlings. The experimental design was completely randomized with five treatments, five replications with 50 seeds per plot. The treatments corresponded to the use of four methods for breaking seed dormancy. In the control treatment (T1), the seeds were not scarified; (T2) thermal scarification at 80ºC from two hours; (T3) thermal scarification in water at the temperature of 100ºC for two hours; (T4) the seeds were submitted to mechanical scarification in aluminum can previously pierced with circular movements for four minutes for 250-seed samples, (T5) the seeds wee submersed in 20 L of water containing 500 g of caustic soda for two hours. The number of emerged seedlings (NPE, %), the length of the seedlings' shoot (CPA, cm), the leaf length (CF, cm), the root length (CR, cm) and dry matter (DM, g) were evaluated. The previous cooling of açaí fruits is not indicated because it reduces the percentage of seed emergence and initial seedling development. Higher emergence of percentage and initial seedling development of açaí are obt...

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The objective of this study was to estimate coefficients of repeatability, to determine the minimum number of fruits necessary for genotype selection and to estimate phenotypic correlation coefficients between morpho-agronomic characters of Theobroma grandiflorum fruits. It was evaluated twenty - two genotypes of an agroforestry system implanted in the municipality of Cantá - RR. Ten fruits per genotype were collected and evaluated for longitudinal length, transverse diameter, total weight, peel thickness, peel weight, pulp weight, placental weight and wet seed weight. Four statistical methods were used to estimate the repeatability coefficients: variance analysis, main components based on the correlation matrix and the covariance matrix, and structural analysis based on the correlation matrix. The number of measurements needed to predict the real value of the genotypes and the Pearson correlation coefficients among the characters were also estimated. The repeatability coefficients ranged from low to moderate, with 10 fruits per plant generally required, with 85% of confidence, in order to make an effective selection for most of the characters studied. There are possibilities of indirect gains for fruits with greater amount of pulp through the selection of larger and / or heavier fruits.

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