Pregerminative treatments of yellow mombin ( Spondias mombin L.) seeds

The germination of Spondias mombin seeds is slow and irregular - it takes between 6 and 24 months for the process to complete. This causes serious difficulties to the plantlet producer since the plantlets are more expensive to produce and frequently are of different heights. The objective of this project was to establish techniques and strategies of yellow mombin (Spondias mombin L.) seed selection to promote and speed up germination. Having that in mind, two experiments were carried out. In the first, seeds (which are of the nucular type) of two colors (beige and brown) and four classes of size (small, medium-small, medium-large, and large) had their length, width, and weight determined. In the second experiment, the color (beige and brown) classified seeds were submitted or not to a fungicide treatment and to mechanical scarification of the endocarp (base, apex, lateral, and no scarification). The experiments were distributed according to a completely random design with four 20 seeds replications in the following factorial arrangements: 4x2 (size x color) and 4x2x2 (scarification x color x fungicide). Seedling emergence in sand, first count of germination, and mean time for germination were weekly determined up to 730 days; these evaluations were based on the determination of normal seedlings counting. Choosing brown and medium-large seeds is an efficient strategy to accelerate seedling emergence. Treating the seeds with fungicide was harmful to the germination process. The lateral scarification of brown seeds permitted a reduction in the period necessary for the completion of germination from 489 to 336 days. As sementes de cajá apresentam germinação lenta e desuniforme, pois o processo normalmente tem duração de seis meses e dois anos. Tal característica constitui-se em entrave para os viveiristas, pois onera os custos de produção e resulta em mudas com tamanhos diversos. O objetivo deste trabalho foi estabelecer técnicas e estratégias de seleção de sementes de cajá (Spondias mombin L.) que promovam ou acelerem a germinação. Para tanto, foram realizados dois experimentos. No primeiro, foram avaliadas sementes (nuculânios) de duas cores (bege e marrom) e quatro classes de tamanho (pequena, média-pequena, média-grande e grande) caracterizadas por meio do comprimento, largura e massa. No segundo experimento, as sementes classificadas quanto à cor (bege e marrom) foram submetidas ou não à aplicação de fungicida e à escarificação mecânica do endocarpo (base