Seed metrics and influence of temperatures and pre-germination treatments on germination of Libidibia ferrea seeds

The objective of this study was to evaluate seed metrics, optimum temperature for germination and efficiency of five pre-germination treatments for overcoming dormancy of L. ferrea seeds. Seeds were subjected to constant temperatures of 15, 20, 25, 30 and 35 degrees C and to the following pre-germination treatments: nicking with pincers; immersion in water for 24 hours at room temperature; scarification with sandpaper; immersion in caustic soda for 60 minutes; and control (untreated seeds). Germination rate was assessed by germination percentage and germination speed index. The biometric characteristics of the evaluated seeds were: longitudinal length, width and thickness, using a digital caliper with a precision of 0.05 mm. A completely randomized design was used with four replicates and means were compared by Tukey test at 5% probability. The best germination performance was obtained in the 15-30 degrees C temperature range and by using chemical scarification with immersion in caustic soda, and mechanical scarification by nicking with pincers and by rubbing on sandpaper.