Innovative techniques for storing wheat seeds at ambient temperature and under refrigeration

Abstract

In Southern Brazil, ambient temperatures are high between wheat harvest and sowing of the new crop, posing a challenge for seed conservation. Therefore, to maintain physiological quality and productive potential, seeds need to be properly stored. This study evaluated the impact of different atmospheric conditions and the application of nitric oxide (NO) on the conservation of wheat seeds stored at different temperatures. Wheat seeds ‘ORS Feroz’ were stored under the following conditions: control, modified atmosphere (MA), two NO concentrations (50 and 500 µL L-1), controlled atmosphere (CA) with high CO2 (50 kPa) and combined with low O2 (1 kPa O2 + 50 kPa CO2), all under two temperatures: exposed to the environment and refrigerated (10 ºC). After five months, germination, vigor, electrical conductivity, and emergence in seedbeds were evaluated. Refrigeration preserved better seed viability, with less vigor loss and lower electrical conductivity compared to exposure to ambient temperature. At ambient temperature, CA (both with high CO2 or combined with low O2) and NO (500 µL L-1) were highlighted in maintaining quality. However, MA also preserved seed quality, even at ambient temperature, and is a lower cost strategy. It can be concluded that storage techniques such as atmosphere control (MA and CA) and NO treatment (500 µL L-1) can be important strategies to prolong wheat seed viability, especially when refrigeration system is not adopted.