Qualea grandiflora Mart.: TEMPERATURA NA GERMINABILIDADE DE SEMENTES

Qualea grandiflora Mart. occurs in riverine forests and in 'cerrado' areas, popularly known as 'pauterra'. With the purpose of obtaining information about the reproductive spread of this species, it was studied the effect of temperature on seed germination capability. The temperatures used were: 15, 20, 25, 30, 35 and 40 \ub0C. The seeds were sown on paper towel in roll form, with four replicates of one experimental unit consisted of a roll with 25 seeds. The experiment followed a completely randomized design with six treatments and four replications. There was primary root emission at temperatures of 15 to 40 \ub0C. Values between 78 % and 93 % were obtained in a wide range of temperatures between 15 and 35 \ub0C. A normal seedling occurred in narrower range, between 20 and 35 \ub0C. The protrusion of the root began on the seventh day after sowing, except the 15 \ub0C which provided a slow and gradual process, beginning on the fourteenth day after hatching. At 40 \ub0C, the germination capability was less than 15 % and there was no normal seedling. For the seed germination of 'pau-terra', it is recommended that the temperature range between 20 and 30 \ub0C.Qualea grandiflora Mart. ocorre em matas de galeria e cerrado, sendo conhecida popularmente como pauterra. Com o objetivo de obter informa\ue7\uf5es sobre a propaga\ue7\ue3o reprodutiva dessa esp\ue9cie foi estudado o efeito da temperatura sobre a germinabilidade das sementes. As temperaturas utilizadas foram: 15, 20, 25, 30, 35 e 40 \ub0C. As sementes foram semeadas em substrato papel-toalha, na forma de rolo, com quatro repeti\ue7\uf5es, sendo a unidade experimental constitu\uedda por um rolo com 25 sementes. O experimento seguiu o delineamento inteiramente casualizado com seis tratamentos e quatro repeti\ue7\uf5es. Houve emiss\ue3o de raiz prim\ue1ria em temperaturas de 15 a 40 \ub0C. Valores entre 78 e 93 % foram obtidos numa ampla faixa de temperaturas, entre 15 e 35 \ub0C. A forma\ue7\ue3o de pl\ue2ntulas normais ocorreu em faixa mais restrita, entre 20 e 35 \ub0C. A protrus\ue3o de raiz iniciou no s\ue9timo dia ap\uf3s a semeadura, exceto a 15 \ub0C que proporcionou um processo lento e gradativo, iniciando no d\ue9cimo quarto dia ap\uf3s a incuba\ue7\ue3o. A 40 \ub0C a germinabilidade foi inferior a 15 % e n\ue3o houve forma\ue7\ue3o de pl\ue2ntulas normais. Para germina\ue7\ue3o de sementes de pau-terra, recomenda-se a faixa de temperatura entre 20 e 30 \ub0C