Storage of soybean seeds: Packaging and modified atmosphere technology

ABSTRACT The characteristics of materials used in packages for seed storage may have a negative influence in the deterioration process, causing future problems during the period of storage and in emergence in the field. In this study, the objective was to evaluate the physiological quality of soybean seeds, stored in different packages with and without the addition of CO2 (modified atmosphere), for different periods of storage and in uncontrolled environmental conditions. In order to carry out the experiment, a completely randomized design was used in a split-plot scheme, with three types of packages (permeable, hermetic package inside the permeable package and hermetic package inside the permeable package with CO2 injection) in the main plot and six storage periods (zero, 45, 90, 135, 180 and 225 days) in the subplot, with four repetitions, totaling 72 experimental units. In hermetic packages multi-layer paper was used with or without CO2 injection, stored them for 225 days and performed an assessment at regular intervals of 45 days. At each period, the seeds were submitted to tests for moisture content, germination, seedling emergence, accelerated aging and electrical conductivity. The hermetic package, with and without CO2 injection, decreases the speed of deterioration of soybean seeds. The hermetic package allows a higher physiological quality of soybeans compared to the permeable package, with a storage period of up to 180 days under uncontrolled environmental conditions. The addition of CO2 inside the hermetic packages favors the maintenance of the physiological quality of soybean seeds in storage.