Qualidade fisiológica das sementes de cupuaçu (Theobroma grandiflorum)

Abstract

Cupuaçu (Theobroma grandiflorum) seeds are classified as recalcitrant, meaning they are highly sensitive to water loss and therefore do not tolerate long storage periods without compromising their physiological quality. This study aimed to evaluate the physiological quality of cupuaçu seeds subjected to different storage periods, seeking to identify possible changes in their viability and vigor over time. The experiment was conducted at the Federal Institute of Education, Science and Technology of Amapá (IFAP), Porto Grande Agricultural Campus. The methodology involved collecting seeds at the Matapi Agricultural Colony. To avoid contamination, excess mucilage was removed with scissors and sand sterilized in an oven, and fungicide was applied. A completely randomized design (CRD) was used, testing four storage times (0, 3, 5, and 10 days) with four replicates. The seeds were evaluated for germination (G), emergence speed index (ESI), moisture, dry matter (DM), and root and shoot length (RSL). The germination test was performed in a laboratory in a BOD incubator at 25 °C, following the Rules for Seed Analysis (RAS). The results showed that the moisture content of the seeds presented a significant difference between treatments. However, the different storage times did not cause significant differences in germination, with percentages above 90%, a result considered satisfactory for the species. The Emergence Speed Index (ESI) followed the same behavior, showing no significant difference between the times. The length and wet and dry mass of the root system also did not show statistical differences between storage times, indicating that the period of up to 10 days did not compromise the initial physiological vigor of the roots. In contrast, the length and wet and dry mass of the shoot were influenced by storage. Storage times of 0 DA and 3 DA yielded superior results for these shoot variables. It was concluded that, although germination and IVE (index of vigor) were not affected, the vigor variables associated with the shoot showed sensitivity to longer storage times. The results reinforce the need for proper management to avoid significant moisture loss and physiological deterioration of cupuaçu seeds.