GERMINATION AND MORPHOLOGY OF SEEDS AND SEEDLINGS OF Parkia gigantocarpa FABACEAE: MIMOSOIDEAE

Parkia gigantocarpa is a valuable timber tree, and due to its rapid growth and great survival can be used to enrich forest clearings. The aims of this study was describe main morphological characters of seeds and seedlings, and to evaluate germination and initial growth of the species at six temperatures. The seed shape varies from elliptical, oblong or ovoid with bone consistency surface, smooth, glossy black color and presence of pleurogram. Average dimensions were 21.25 mm (length), 10.43 mm (width), and 6.15 mm (thickness). The embryo type is linear axial, with fleshy cotyledons, convex planes and dominant. The germination is epigeous phanerocotyledonary with fleshy cotyledons, and occurs between the second and fifth days after sowing. The fully developed seedling stage was reached on the fifteenth day after sowing. Temperatures of 30 and 35 C provided higher germination rates in less time and with higher root biomass allocation.Keywords: Amazon; biometrics; germination temperature; fava-atanã; forest seeds. AbstractParkia gigantocarpa is a valuable timber tree, and due to its rapid growth and great survival can be used to enrich forest clearings. The aims of this study was describe main morphological characters of seeds and seedlings, and to evaluate germination and initial growth of the species at six temperatures. The seed shape varies from elliptical, oblong or ovoid with bone consistency surface, smooth, glossy black color and presence of pleurogram. Average dimensions were 21.25 mm (length), 10.43 mm (width), and 6.15 mm (thickness). The embryo type is linear axial, with fleshy cotyledons, convex planes and dominant. The germination is epigeous phanerocotyledonary with fleshy cotyledons, and occurs between the second and fifth days after sowing. The fully developed seedling stage was reached on the fifteenth day after sowing. Temperatures of 30 and 35 C provided higher germination rates in less time and with higher root biomass allocation.Keywords: Amazon; biometrics; germination temperature; fava-atanã; forest seeds. ResumoGerminação e morfologia de sementes e plântulas de Parkia gigantocarpa Fabaceae: Mimosoidae. Parkia gigantocarpa é uma árvore de interesse madeireiro, indicada para o enriquecimento de clareiras devido seu rápido crescimento. Os objetivos deste trabalho foram descrever os principais caracteres morfológicos de sementes e plântulas, e avaliar a germinação de sementes e desenvolvimento inicial da espécie em seis temperaturas. As sementes apresentam formato que varia de elíptica, ovóide ou oblonga com superfície de consistência óssea, lisa, brilhosa de coloração negra e presença de pleurograma, com dimensões médias de 21,25 mm de comprimento, 10,43 mm de largura, e 6,15 mm de espessura. O embrião é do tipo axial linear, com cotilédones crassos, plano convexos e dominantes. A germinação é epígea fanerocotiledonar com cotilédones carnosos, e ocorre entre o segundo e quinto dias após semeadura, sendo que o estágio de plântula completamente formada é alcançado no décimo quinto dia após a semeadura. As temperaturas de 30 e 35 ºC proporcionaram elevadas taxas de germinação em menor tempo e com maior alocação de biomassa radicular.Palavras-chave: Amazônia; biometria; temperatura para germinação; fava-atanã; sementes florestais