Morphological characterization of fruit, seed and seedling and germination of Hymenaea courbaril L. (Fabaceae) ('Jatobá')

Abstract This study has aimed to characterize the morphology of fruit, seed and seedling and evaluate the germination of Hymenaea courbaril L., under different substrates and temperatures. The physical characteristics were determined, as well as the morphological description of the internal and external parts of fruits and seeds, stages of germination and early seedling development. Germination tests were conducted in a completely randomized design, in a 3x2 factorial scheme, with three temperatures (20 °C, 25 °C and 30 °C) and two substrates (sand and vermiculite), with six plots of 30 seeds. The germination percentage, germination speed index (GSI) and mean germination time (MGT) were calculated. The fruits are dry and woody and the seeds are exalbuminous, with an axial embryo. The germination is epigeal and the seedling is phanerocotylar. The combination of vermiculite or sand associated to temperatures of 25 °C or 30 °C is effective for conducting the germination tests.摘要 本研究旨在明确孪叶豆（Hymenaea courbaril L.）的果实、种子及幼苗形态特征，并探究不同基质与温度条件下其种子萌发特性。本研究测定了该物种的物理性状，并对果实与种子的内外结构、萌发阶段及幼苗早期发育过程开展了形态学描述。萌发试验采用完全随机设计，设置3×2因子组合：3个温度梯度（20℃、25℃、30℃）与2种基质（沙子、蛭石），共设6个重复组，每组含30粒种子。本研究计算了种子发芽率、发芽速度指数（GSI）与平均发芽时间（MGT）。果实为木质干果，种子无胚乳，具轴状胚。萌发类型为出土萌发，幼苗具外露子叶。采用蛭石或沙子作为基质，搭配25℃或30℃的温度条件，可有效开展该物种的种子萌发试验。