Influência de tratamentos pré-germinativos, temperatura e luminosidade na germinação de sementes de leucena, cv. Cunningham

Abstract

This research was carried out in two experiments with the objective of identifying methods to overcome dormancy in seeds of Leucaena leucocephala, Cunningham cultivar, and to verify the effect of light and temperature in the germination of this specie. In first, the seeds were submitted to ninemethods to overcome dormancy: immersion in water under ambient temperature during 24, 48 and 72 hours; immersion in hot water under temperatures of 60, 80 and 100 oC; immersion in sulfuric acid during 5 and 10 minutes, besides the control. In the second experiment, after treatment with sulfuric acid for 10 minutes, the seeds were sowed Germitest in a paper towel Germitest and put to germinate under ten combinations: continuous light and constant temperature of 20, 25, 30 and 35 oC; absence of light and constant temperature of 20, 25, 30 and 35 oC; alternate temperature of 20-30 and 25-35 oC, both with fotoperiod of eight hours. It was concluded that the specie Leucaena leucocephala is characterized by seed dormancy and the immersion in sulfuric acid is an efficient method to overcome this problem; the seeds of leucena are insensitive to the light and their germination was not influenced by the applied temperatures.