Superação de dormência e pré-germinação de sementes de Leucaena leucocephala

Abstract

The objective of this study was to evaluate alternative methods to overcome dormancy in Leucena (Leucaena leucocephala) seeds. The seeds were collected from four different matrices and subsequently submitted to different treatments with mechanical scarification and immersion in water and soft drink at different times (0, 6, 24 and 48 h) at 25 ºC. A completely randomized design was used, consisting of 14 treatments composed of four replications containing 50 seeds each. The variables analyzed were: Germination at the first count (G); Normal Seedlings (PN); Hard or Dormant Seeds (SD); and Germination Speed Index (IVG). The results increased higher percentages of germination (G) in the T1 treatment (mechanical scarification) with 46.7 and 43.2% of normal seedlings (PN) with 43.2% and IVG of 41.9. However, when observing only the treatments submitted in different combinations, it was noted that the treatments T8 (Mechanical scarification and immersion in soda for 6h at 25 ºC) and T2 (Mechanical scarification and immersion in distilled water for 6h at 25 ºC) presented a germination of 44.7 and 39.7%, respectively. Thus, shorter water immersion times associated with mechanical scarification are required to obtain the highest percentage of germination and formation of normal seedlings.