Vermiculite as substrate for germination of \u2018barbatim\ue3o\u2019 seeds

O objetivo deste trabalho foi avaliar o desempenho da vermiculita como substrato para o teste de germina\ue7\ue3o e estabelecer qual granulometria e intensidade de umedecimento deste substrato seria mais favor\ue1vel \ue0 germina\ue7\ue3o de sementes de barbatim\ue3o. A semeadura foi realizada com quatro repeti\ue7\uf5es de 50 sementes (escarificadas com H2SO4/60 min) em rolo de papel (RP) umedecido com 2,5 vezes a massa em \ue1gua (testemunha) e vermiculita nas granulometrias m\uedcron (MI), superfina (SF), fina (F) e m\ue9dia (M) umedecida com 0,5; 1,0; 1,5 e 2,0 vezes a sua massa em \ue1gua. O teste de germina\ue7\ue3o foi conduzido a 30\ub0C, avaliando-se a primeira e a \ufaltima contagens aos 7 e 28 dias ap\uf3s a semeadura realizando-se avalia\ue7\uf5es semanais das pl\ue2ntulas normais. Foi calculado o tempo m\ue9dio e a frequ\ueancia relativa de germina\ue7\ue3o. O teste de germina\ue7\ue3o de sementes de barbatim\ue3o p\uf4de ser realizado em vermiculita F (umedecida com 2,0 vezes a sua massa em \ue1gua) ou M (umedecida com 0,5 at\ue9 2,0 vezes a sua massa em \ue1gua) por possibilitarem a m\ue1xima germina\ue7\ue3o em menor tempo (21 dias), de modo similar ao RP.The objective of this research was to evaluate the use of vermiculite as a substrate for the germination test of \u2018barbatim\ue3o\u2019 seeds and to establish what would be the best granulometry and the best moisture intensity to germinate \u2018barbatim\ue3o\u2019 seeds. Four replications of 50 seeds were previously scarified with H2SO4 for 60 minutes. Afterwards, the following germination substrates were evaluated: paper rolls moistened with water equivalent to 2.5 times the weight of the dry paper (control); micron, super thin, thin and average sized vermiculite moistened with 0.5, 1.0, 1.5 and 2.0 times the weight of the dry paper. The germination temperature was 30\ub0C. The percentage of normal seedlings was obtained seven days after sowing (first count) and, then, weekly (up to 28 days). Average time and relative distribution of germination were calculated. It was concluded that the germination of \u2018barbatim\ue3o\u2019 seeds can be carried out with either fine vermiculite moistened with water equivalent to 2.0 times the weight of the dry paper or average sized substrate moistened with water equivalent to 0.5 to 2.0 times the weight of dry paper. These treatments resulted in higher and faster germination (21 days), similarly to the paper roll method