SUBSTRATE MOISTURE AND TEMPERATURE IN GERMINATION OF Parkia platycephala BENTH. SEEDS

Abstract

A Parkia platycephala Benth. (faveira) \ue9 uma leguminosa arb\uf3rea, conhecida como fornecedora de madeira comercial na Amaz\uf4nia. O presente trabalho foi conduzido com o objetivo de avaliar diferentes volumes de \ue1gua para umedecimento do substrato e temperaturas na germina\ue7\ue3o e vigor de sementes de Parkia platycephala. As sementes foram submetidas ao teste de germina\ue7\ue3o em papel-toalha, organizado na forma de rolos e umedecido com volumes de \ue1gua equivalentes a 2,0; 2,5; 3,0 e 3,5 vezes o peso seco do substrato e colocadas nas temperaturas constantes de 20, 25, 30 e alternada de 20-30\ub0C. Foram avaliados: a porcentagem de germina\ue7\ue3o, a primeira contagem de germina\ue7\ue3o e o \uedndice de velocidade de germina\ue7\ue3o, o comprimento e a massa seca da raiz e da parte a\ue9rea das pl\ue2ntulas normais. O delineamento experimental foi o inteiramente ao acaso, com os tratamentos distribu\ueddos em esquema fatorial 4 x 4 (quatro volumes de \ue1gua e quatro temperaturas). O umedecimento do substrato com 2,0; 2,5; 3,0 e 3,5 vezes o peso do papel nas temperaturas de 25, 30 e 20-30\ubaC pode ser utilizado para avalia\ue7\ue3o da germina\ue7\ue3o e vigor das sementes de Parkia platycephala Benth. A temperatura de 20\ubaC em todos os volumes de \ue1gua testados para umedecimento do substrato reduziu a germina\ue7\ue3o e o vigor das sementes.The Parkia platycephala Benth. (faveira) is a leguminous tree, known as a provider of commercial wood in the Amazon rain forest. This study aimed to evaluate the effects of different volumes of water for substrate moisture and temperatures on germination of Parkia platycephala. After this, they were sowing over towel paper, organized in rolls wetted with water contents equivalent to 2.0; 2.5; 3.0 and 3.5 times the weight of the substrate without new water addition, and they were maintained in chambers at constant temperatures of 20, 25, 30\ub0C and alternate temperature 20-30\ub0C. The following parameters were analyzed: the germination percentage, first count germination, index of germination speed, length and dry mass of seedlings (shoot and root). A completely randomized design was used with a 4 x 4 factorial (water volumes and temperatures). The moistening of the substrate with 2.0, 2.5, 3.0 and 3.5 times the weight of the paper at temperatures of 25, 30 and 20-30\ubaC can be used for germination and vigor of Parkia platycephala Benth. The temperature of 20\ubaC and all volumes of water tested for wetting the substrate reduced the germination and the vigor of these seeds