Aspectos da germinação de sementes de assa-peixe (Vernonia polyanthes Less.).

The objective of this research was to evaluate the effect of temperature and light on germination of Vernonia polyanthes Less. seeds. Therefore were tested six constant temperatures (15, 20, 25, 30, 35 and 40°C), and four combinations of alternating temperatures (15-20, 15-25, 20-30 and 20-35°C) in the presence and absence, which was provided during periods of higher temperatures, when evaluating the rotation. The variables evaluated were: degree of moisture, germination and vigor (first count of germination and speed of germination). The completely random design was used and the results were submitted to analysis of variance with means compared by Tukey test at 5% probability. Seeds of the Vernonia polyanthes species are preferential photoblastic with germination favored in the presence of light. The highest percentage of germination and seed vigor levels of the seeds of V. polyanthes were obtained in temperatures of 25°C constant and alternating 15-25°C in the presence of light. [ABSTRACT FROM AUTHOR]