Abstract:To explore the physiological response mechanism of Michelia macclurei seeds under different storage temperatures and conditions, the viability, germination rate, moisture content, physiological and biochemical indicators were determined. The results showed that with the extension of storage time, the viability, germination rate, protein content, and activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and amylase (AMY) of the seeds all showed a downward trend; the contents of soluble sugar and malondialdehyde (MDA) first increased and then decreased, and the MDA content after storage was always significantly higher than that before storage. The moisture content of seeds stored at 4 ℃, –20 ℃ and –196 ℃ showed a trend of first decreasing and then increasing; among them, the seeds stored at 4 ℃ and –196 ℃ had higher viability, germination rate, soluble sugar and protein content, as well as SOD, POD, CAT and AMY activities. In addition, retaining the pseudocarp significantly increased the viability and germination rate of the seeds. The germination rate and viability were significantly or extremely significantly correlated with contents of moisture, soluble sugar, protein and MDA, as well as activities of SOD, POD, CAT and AMY. Storage temperature, storage duration and the removal of pseudocarp all had significant effects on the physiological and biochemical indicators of M. macclurei seeds. Therefore, in the actual storage process, low temperature (such as 4 ℃ or –196 ℃) combined with pseudocarp protection could be adopted to maintain the physiological activity of M. macclurei seeds to the greatest extent and extend their storage life.
