QUALIDADE FISIOLÓGICA E COMPOSIÇÃO PROXIMAL DE SEMENTES DE SORGO BENEFICIADAS EM MESA DENSIMÉTRICA E ARMAZENADAS

Abstract

Sorghum bicolor L. Moench is an extremely important crop in Brazil, and it is used for human and animal food. However, there are few studies regarding this culture conservation and the efficiency of sorghum seed production process, which requires greater and detailed studies on the subject. Taking in consideration the few studies on the influence on using the densimetric table on seed processing and its respective transfer, this study aimed to evaluate the physiological quality and proximal composition of sorghum seeds from the densimetric table transfer during the storage for three months. Initially, the seeds were submitted to drying process. They were cleaned in air machines and sieves, then classified by size, and processed on a densimetric table. The treatments consisted of four collection points on the end of the densimetric table: (a) higher end (P1); (b) upper middle part (P2); (c) middle part (P3); and (d) lower end (D). Later, the transfers were separated into higher end (P3R1) and lower end (P3R2) in a total of six treatments. Seeds were analyzed regarding water content, electrical conductivity, germination, first count, seedling length, seedling dry mass, germination speed index, seedling emergence in sand, emergence speed rate, accelerated aging, color, proteins, carbohydrates, ash, and lipids. They were stored under an air-conditioned environment, using a completely randomized design, and the means were compared by the Tukey test at 5% significance. It is concluded that: (a) the transfer of sorghum seeds can also improve the physical quality of a batch at the end of the stages due to its standardization, contributing to improve the physiological quality; b) although germination rate remained high during storage, dry mass (DM) and length of normal seedlings (LNS) were negatively influenced viii by time; (c) the seeds collected at the upper exit of the gravity table presented better quality attributes, regardless of the analyzed batch; d) the performance of the gravity table allows the removal of the seed fractions with lower specific mass and promotes positive changes in the physiological quality of sorghum seed batches; e) time had a positive influence on the variables ash and protein content, increasing their values, but the opposite occurred for the carbohydrate content, reducing their value during storage; and f) the transfer of sorghum seeds improved the quality of the lipid content in the batch, ensuring an assertive stratification and maintaining the quality at the high points of the densimetric table, both in processing and in transfer.