Methodology adjustment for the germination test of red pitaya seeds/Adequacao da metodologia para o teste de germinacao de sementes de pitaia vermelha

Hylocereus undatus (Haw.), popularly known as red pitaya is a cactus for which it has been registered an increase in consumption in recent years and, being as yet little explored, several aspects related to its propagation are still unknown. Yet, there are no criteria for the performance of germination tests for seeds of this species published in Rules for Seed Analysis. Accordingly, the objective of this research was to adapt the methodology to the substrate, temperature and time of initial and final count for the germination test. Four substrates were tested (rolled paper, sand, vermiculite and soil) and four temperatures (20, 25, 30 e 20-30°C).The effect of substrates on the seeds germination performance was evaluated by the germination test and first count installed with four replicates of 50 seeds. The number of seedlings was counted daily until they achieved stability. The percentage of seed germination was evaluated at the end of the experiment, considering the normal and abnormal seedlings and dead seeds. It was concluded that the germination test of red pitaya seeds must be performed at constant temperature of 250C in rolled paper, with initial and final counts at five and ten days after sowing, respectively. Key words: Hylocereus undatus (Haw.), cactus, temperature, substrate. Hylocereus undatus (Haw.), popularmente conhecida como pitaia vermelha e uma cactacea para a qual se tem registrado um aumento de consumo nos ultimos anos e, por ser ainda pouco explorada, varios aspectos referentes a sua propagacao ainda sao desconhecidos. Ate o momento, nao existem criterios para a execucao de testes de germinacao para sementes dessa especie, publicados nas Regras para Analise de Sementes. Nesse sentido, objetivou-se com este trabalho adequar a metodologia quanto ao substrato, temperatura e tempo de contagem inicial e final para o teste de germinacao. Foram testados quatro substratos (rolo de papel, areia, vermiculita e solo) e quatro temperaturas (20, 25, 30 e 20-30°C). O efeito dos substratos no desempenho germinativo das sementes foi avaliado pelo teste de germinacao e de primeira contagem instalado com quatro subamostras de 50 sementes. Foram feitas contagens diarias do numero de plantulas emergidas ate atingirem a estabilidade e, no final do experimento, foram avaliados a porcentagem de germinacao das sementes, considerando as plantulas normais, anormais e sementes mortas. Concluiu-se que o teste de germinacao de sementes de pitaia vermelha deve ser