Physiological performance of wheat seeds as a function of moisture content at harvest and storage system

Abstract

The physiological performance of wheat seeds may be influenced by the harvest season and storage system. This study aimed at evaluating the physiological performance of wheat seeds as a function of different moisture contents at harvest, with later storage under hermetic and conventional systems. Harvest was performed when the seeds reached moisture contents of 28.6 %, 18.5 % and 12.9 %. Subsequently, they were stored for 240 days, in both systems, at room temperature. The evaluation of seed physiological performance was carried out by germination and vigor tests, shoot length and dry matter of seedlings. The germination of wheat seeds stored under the hermetic system increased up to 180 days of storage, due to the seed dormancy breaking, with a subsequent decrease of the values, while those stored under the conventional system showed a linear decrease of germination throughout the storage. The hermetic system provided an increase in seed vigor up to 120 days of storage and, after this period, there was a reduction of the values. The conventional system promoted a linear reduction of seed vigor throughout the storage, except for the results obtained in the tests of first germination count and germination speed index, which showed an increase up to 60 days of storage. Harvest delay negatively influenced seed germination and vigor, regardless of time and storage system. The combination of harvest anticipation and hermetic storage improves the physiological performance of seeds over time.