Drying and storage of Melanoxylon brauna Schott. seeds

Abstract

The objective of this work was to evaluate the sensitivity of Melanoxylon brauna Schott. tree legume seeds to desiccation and storage. In the drying experiment, the Melanoxylon brauna seeds were submitted to two drying conditions: a forced air circulation chamber (40.18 °C ± 0.13 and 28.48% ± 3.95 RH) and a silica gel desiccator (27.19 °C ± 1.28 and 26.19% ± 0.94 RH) for different times (0, 12, 24, 36, 72, and 144 hours). A completely randomized design in a 2 (drying methods) × 5 (drying times) factorial scheme plus control and 4 replications of 25 seeds was used. The following variables were evaluated before and after drying: seed moisture content, percentage of germinated seeds, germination speed index, percentage of mortality, normal and abnormal seedlings. In the storage experiment the seeds were divided into two batches: pre-dried (at 5.0% humidity) and without drying (control at 8.9% humidity). The seeds were then stored in plastic bags in three environments: refrigerator at 5 °C, freezer at –20 °C and room temperature (29 °C). The seeds were removed every four months and submitted to the humidity and germination test for 24 months. Data from this storage experiment were analyzed considering a randomized block design in a 2 (drying levels: presence and absence) × 3 (storage environments: refrigerator, freezer or room temperature) factorial scheme + 2 controls (with and without drying at baseline) and 4 repetitions of 25 seeds. Drying reduced initial seed water content from 8.9% to 5.0%, without loss of viability. Drying in the chamber at 40 °C was faster and more efficient than in silica gel. The results enable classifying the seeds of this species as orthodox, i.e. tolerant to desiccation. The fridge and freezer were efficient for storing the Melanoxylon brauna seeds up to 24 months, independent of previous drying, while storing the seeds at room temperature with previous drying makes them last longer than without drying, as the seeds can last up to 16 months with drying, or 12 months without drying.

Physiological Quality of Stored Dipteryx alata Vogel Seeds: Tetrazolium Test and Radiographic Imaging Standardization

“…In accordance with the germination data obtained herein, seedling emergence evaluations indicate that baru seeds remained viable during storage (Figure 4 D). What was also verified in seeds of Melanoxylon brauna Schott, by Freire et al (2021) who observed high percentages (85%) of germination, when it is were maintained in a refrigerator at ± 4 ºC for up to 12 months with a water content close to 5%. Once in studies by Ribeiro et al (2018) was noted that seeds of Erythrina velutina Willd., stored at 10 ºC for up to 14 months registered germination above 90%, however, showed oscillation in the rate of seed moisture after six months of storage.…”

Viability of Mimosa caesalpiniifolia Benth. seeds as a function of fruit maturity stage and storage temperature

“…The observed results indicate that storage for 12 months in an environment without temperature control (mean of 24 °C) enhances the process of deterioration of M. caesalpiniifolia seeds. Storage at room temperature also promoted faster loss of viability of Caesalpinia echinata seeds, at three months (Hellman et al, 2006), Tabebuia caraiba seeds, at three months (Guedes et al, 2012b), Myracrodruon urundeuva seeds, at 150 days (Guedes et al, 2012a) and Melanoxylon brauna seeds, at 24 months (Freire et al, 2021), compared to colder temperatures.…”