Seed germination at different stratification temperatures and development of Phytelephas macrocarpa Ruiz & Pavon seedlings

Phytelephas macrocarpa (ivory palm) is an Amazonian palm vulnerable to exploitation pressure, as its seeds are widely used in regional handicrafts. The aims of this study were to evaluate the effectiveness of different stratification temperatures in overcoming seed dormancy and to analyze the seedling development stages of this species. In germination under stratification, the seeds were placed in plastic bags containing moistened vermiculite, and maintained at the constant temperatures of 25, 30, 35 and 40 degrees C, and an alternating temperature from 26 to 40 degrees C. In the study about the development of seedlings, seeds were sown in vermiculite under plastic cover (growing house), and the evolution of the seedling was evaluated, from the formation of germinative button to the complete blade expansion of the first eophyll. Stratification at alternating temperatures (26 to 40 degrees C) helped overcoming seed dormancy. Stratification at 25 degrees C kept the seed viability for nine months. Germination, characterized by the formation of the germinative button took an average of 114 +/- 24 days, and the seedling development until the first extended eophyll lasted 244 +/- 57 days.