A technological approach to the morphofunctional classification of seedlings of 50 Brazilian forest species

Gabriela Alves Lobo,Luciana Salazar Rehbein,Denise Garcia De Santana,Antonieta Nassif Salomão,Angélica Polenz Wielewicki

doi:10.1590/s2317-15372014000100011

Abstract

A technological approach to the morphofunctional classification of forest species seedlings defines the essential structures in the evaluation of germination testing and identifies changes in this structures that suggest abnormalities. The objective was to associate morphofunctional seedling classification to seed germination testing using official germination methods for 50 forest species from Amazon, Caatinga, Cerrado, Atlantic Forest and Pantanal biomes. Morphofunctional classification and abnormalities were defined using seedlings from 232 germination pre-tests and 1,160 samples that were formed for each species using seeds from distinct locations and with at least three levels of vigor. The phanero-epigeal germination with a non-developed epicotyl predominated among species (84%). Common in hypogeal germination, the development of the epicotyl occurred only in seedlings of Anadenanthera colubrina and Erythrina speciosa, both with epigeal germination. The need to supply and sustain the great mass produced in its long life cycle, the presence of the primary root was considered essential for the normal seedling classification of these forest species. Curled, stunted, necrotic, bifurcated primary root and those retained in the seed coat or in the fruit structures, were the main abnormalities of the seedling root systems. Damages to the shoot system were uncommon.

Highlights

Germination measurements such as capacity, time, velocity, synchrony and uniformity contribute to the understanding of the germination process (Ranal and Santana, 2006)
Most of the seedlings of these 50 forest species had cotyledons that were detached from the seed coat or the epicarp, developed hypocotyl and non-developed epicotyl (Table 1)
The prevalence of phaneroepigeal seedlings is not restricted to this group of 50 Brazilian forest species

Summary

Introduction

Germination measurements such as capacity, time, velocity, synchrony and uniformity contribute to the understanding of the germination process (Ranal and Santana, 2006) These same measurements are dependent on experimental conditions during germination testing and cannot be used to group species. Conservative characteristics such as seedling morphology and structural functionality do make it possible to organize classification systems (Miquel, 1987; Garwood, 1996). In this context after conducting a floristic survey of the tropical forest tree species from Panama, Garwood (1983; 1996) symbolized five seedling classifications of Miquel (1987), categorizing cotyledons based on exposure, position, texture and function during germination. Miquel’s classification has been expanded (Ferraz and Calvi, 2011)

Methods

Results

Conclusion