Study indicates advantages of airtight bags for storing corn seeds

The quality of corn seeds may decline during storage. Factors such as relative humidity, temperature and oxygen concentration are decisive for preservation. Low-oxygen atmospheres have been shown to be effective in laboratory experiments for improving seed germination and vigor. However, the application of this technology on a larger scale, with bags weighing 25-50 kg, is still little explored. A recent study evaluated the feasibility of using low-oxygen atmospheres to store corn seeds in airtight 25 kg bags made of polyethylene and polyamide under controlled conditions.

Researchers investigated the airtight bags' ability to maintain low oxygen levels over time. They then compared the germination and vigor of seeds stored in these bags under modified and self-modified atmospheres with seeds stored in traditional polypaper bags under normal atmospheric conditions. Seeds had 14% moisture and were stored at 25°C and 10°C.

The results indicated that it was feasible to maintain low oxygen levels in the polyethylene-polyamide bags. At 25 °C, modified and self-modified atmospheres maintained higher germination values ​​(95,8% and 94,4%, respectively) compared to traditional storage (68,3%), and both were as effective as refrigeration (97,6%). However, refrigeration was better at preserving seed vigor, with root emergence values ​​of 85,2% in self-modified atmospheres and 78,9% in modified atmospheres, compared to 65,0% and 61,2%, respectively, at 25 °C.

Methodology, results and discussion about the study

The study evaluated airtight polyethylene and polyamide bags with a capacity of 25 kg. Seeds stored in modified and self-modified atmospheres were compared with seeds stored in traditional polypaper bags under normal conditions. Seeds had 14% moisture and were stored at 25°C and 10°C.

The scientists pointed out that polyethylene and polyamide bags managed to keep the oxygen concentration below the desired limit of 3% for a period of five months. The low oxygen concentration was due to the high hermeticity of the bags, preventing the entry of oxygen from outside. The hermetic valve for gas injection and closing the bags made it possible to achieve a very low initial oxygen concentration (0,65% on average), minimizing oxygen entry.

At 25 °C, modified and self-modified atmosphere technologies were superior to traditional technology and equally effective in preserving germination potential. During the period studied, modified and self-modified atmospheres allowed the same germination values ​​at 25 °C as refrigeration (10 °C). However, for the preservation of root emergence, refrigeration was more effective.

The benefits observed in laboratory experiments were consistent at the pilot scale. The difference in germination was even more pronounced in favor of the low oxygen atmospheres (approximately 95% on average for both modified and self-modified atmospheres versus 68% in the normal atmosphere).

For these reasons, scientists have concluded that polyethylene and polyamide bags are effective in maintaining low-oxygen atmospheres. This technology can significantly improve corn seed preservation, offering a viable alternative when refrigeration is not available. Self-modifying atmospheres, which eliminate the need for external gas injection, are especially attractive. They suggest that future studies should explore this technology in different moisture levels and other seed species.

The study was developed by María Bernadette Abadía, Luciana A. Castillo, Yanela N. Alonso, María Gloria Monterubbianesi, Gisele Maciel and Ricardo E. Bartosik.

More information can be found at mdpi.com/2077-0472/14/8/1268