Biometria de Sementes e Desenvolvimento Pós Seminal de Dipteryx alata, Enterolobium gummiferum E Magonia pubescens, e Influência dos Extratos de Parkia platycephala e do Sombreamento na Germinação e/ou Desenvolvimento Inicial dessas Espécies.

Abstract

Dipteryx alata, Enterolobium gummiferum and Magonia pubescens are Cerrado species that possess functional attributes potentially important for use in restoration plantations, for example, presenting rapid growth and low mortality rates. Taking this into consideration, the present work aimed to evaluate the biometric characteristics as well as the post-seminal development of these species with the purpose of generating information to support future taxonomic, ecological and silvicultural studies as well as conservation and recovery programs of degraded areas. The biometric study was performed by measuring the length, width, thickness and mass of the seeds. For the description and illustration of post-seminal development until seedling formation, 50 seeds of each species were placed to germinate in 14 cm diameter Petri dishes containing two sheets of filter paper moistened with deionized water. The plates were kept in a germination chamber with a temperature of 25ºC. The seeds of D. alata had a mean length, width, thickness and mass of 26.33 mm, 10.92 mm and 7.85 mm and 1.33 g, respectively. Its germination is of the epigeic type fanecotiledonar. The protrusion of the root occurs three days after sowing and the seedling is completely formed approximately on the twelfth day. The seeds of E. gummiferum have mean length, width, thickness and mass 13.90 mm, 8.68 mm, 5.58 mm and 0.43 g, respectively. Its germination is also of the epigeic type fanecotiledonar, beginning on the second day after sowing and the complete formation of the seedling is verified from the twelfth day. The seeds of M. pubescens have an average length, width, thickness and mass of 4.56 cm, 8.72 cm, 2.66 mm and 1.82 g, respectively. Its germination is of the semi-hypogeal cryptocotidelodar type beginning on the third day after sowing and the seedling is completely formed around the twenty-second day.