Main Article Content
This study evaluated the effects of stress caused by the depth of sowing and the amount of sand in the substrate, characterizing the fruit of Hancornia speciosa (Mangaba) from its harvest, germination, until completing 150 days of initial development. For each character evaluated for each depth and substrate, Weibull models were fit and the parameters of the models were compared. A total of 572 fruits collected in three localities in Porto Nacional, State of Tocantins, were analyzed for longitudinal and transverse length, fresh weight, number of seeds and seed weight. The results showed higher values than those found in other studies, indicating that the fruits presented larger size and weight, characteristics desirable by the consumer, although they presented a larger number of seeds/fruit. Germination potential was analyzed in the laboratory, and the effects of sowing depth and percentage of sand in the substrate, on germinability and development, after 150 days of planting, were studied in the greenhouse. Germination percentage values of 74.4% and 51.5% were observed in the laboratory and greenhouse, respectively; mean germination time of 11 and 17 days and synchronization of germination of 2.79 and 2.75. Using the Weibull cumulative distribution to express germination behavior of mangaba, it was observed that the model fitted well to describe the observed data and parameters (G, a, b) served to compare the effect of germination expression over time. Both germinability and initial development characters showed better results when planted at 1 cm depth and in a substrate with up to 15% sand.