Fruit and seed biometry, seeds germination and initial growth of barbatimão (Stryphnodendron adstringens)

Abstract

Abstract

Stryphnodendron adstringens is a tree widely distributed in the Cerrado. Its bark has high tannin content and is heavily exploited due to its astringent action. This research aims to identify biometric characteristics of fruits and seeds, and also assess the effect of temperature, scarifications and storage on germination of its seeds as well as evaluate the initial seedling growth under different conditions of shading. Was also evaluated the seedling response submitted to two levels of shading (0 and 50%) in nursery conditions. Length, width and thickness ranged from 48.1 to 97.0 mm, from 10.1 to 16.9 mm and from 6.4 to 19.6 mm for fruits and from 3.7 to 10.0 mm, 3.1 to 5.7 mm, and 1.6 to 4.4 mm for seeds. The average number of seeds per fruit was 8.2±2.5, 39% damaged seeds. The weight of 1000 seeds was 68.4 g. Mechanical scarification was the most efficient in breaking dormancy, increasing the percentage and germination speed index. The optimum range of germination rate was 25 to 35 ºC and they remained viable after eight months of storage. The results revealed that the species is heliophytic, has slow growth, and is appropriate for planting in degraded areas.

Keywords: Fabaceae; tree species; dormancy; viability.