Physiological and biochemical changes in Cedrela fissilis seeds during storage

The objective of this work was to evaluate the effect of storage on the physiological quality of cedar (Cedrela fissilis) seeds, as well as to correlate the germination and vigor of the seeds with their main biochemical changes. The experiments were carried out in a completely randomized design, in a 3x5 factorial arrangement (three environments x five storage periods). Seeds were stored for 0, 135, 280, 381, and 515 days in: a humidity chamber at 5 +/- 2 degrees C and 80% relative humidity, a drying chamber at 20 +/- 2 degrees C and 60% relative humidity, and an uncontrolled environment (laboratory) at 16 +/- 10 degrees C and 60 +/- 25% relative humidity. In all storage periods, the content of moisture on a wet basis and the percentages of proteins, lipids, total carbohydrates, and ash were evaluated. For the viability and vigor tests, the percentage of germination and mean germination time were calculated. At sampling time, seeds showed 11.5% water content, 85.5% germination, and mean germination time of 13.5 days, and all were negatively influenced by storage period. Protein percentage showed a downward trend, while that of carbohydrates increased as the storage period was extended. Seed germination and vigor reduce drastically with storage.