Desafios da propagação sexuada do umbuzeiro, Spondias tuberos Arr. (Anacardiaceae)

Abstract

Spondias tuberosa is an Anacardiaceae adapted to warm climates, low relative humidity and low water demands. Its form of exploitation is extractive and few are the commercial orchards. There are few studies that select genotypes suitable for the processing industry and in nature commercialization of its fruits. Seed-propagated seedlings have the peculiarity of better surviving periods of water scarcity, due to the development of tubers a few days after germination, thus highlighting the importance of sexual propagation. This presents one of the limiting factors for the propagation of umbuzeiro, the dormancy of its seeds, with a low rate of germination and unevenness. The dormancy can be physical, with tegument resistance to water absorption, gas exchange and embryo expansion or morphological, caused by embryonic immaturity. As a result, this review aims to discuss the main techniques for overcoming numbness of the umbu through the results of the research with this species. Some methodologies suggest pre-germination treatments to standardize and accelerate seed germination, such as imbibition in water or growth regulators, mechanical, chemical and thermal scarification and seed submission to storage. Based on the literature found, the storage of the seeds presents superior results to the other treatments, however, a greater depth of the research will help to validate this technique, because there is still a low speed and irregularity in the germination.