| A study was conducted to the seed storage of P. kaempferi. Artificial accelerated aging has been used to probe the process of seed deterioration, and the method that integrated ultradry storage technology with low temperature storage has been used to investigate physiological and biochemical changes in seed storage. The main results were described as follows:1. Dehydration rate was smaller than other species by using silicone at room temperature. There were no significant differences between seed of MC=16.0% and seeds of 4.2%≤MC≤11.4% in germination percentage, seed vigor index and seedling dry weigh. However, significant differences were showed in both germination percentage and seed vigor index when MC declined to 3.3%.2. During artificial accelerated aging at 50℃, seed of 4.2%≤MC≤5.3% showed the minimal deterioration rate; seed conductivity was increasing when the aging time prolonged and the MC increased:the contents of both O2·- and MDA increased accompanied by the extension of aging time; and the activities of SOD and POD increased accompanied by the extension of aging time when the seed viability was not severely damaged.3. When seed of MC=16.0% stored at room temperature (CK), the content of ABA decreased sharply in the first 180 days and then remained stable; the content of IAA decreased slowly during the early storage time and then remained stable; the content of GA3 increased at first and then decreased; the content of ZR increased notably in the first 180 days, then decreased rapidly and increased steadily in the end. The ratio of GA/ABA was lower than the seed of other treatments and was increasing at first and then decreased. The ratio of IAA/ABA was higher than the seed of other treatments and was increasing steadily. The ratio of ZR/ABA increased during the first 180 days, then decreased before 270 days and increased in the end. The change of (GA+IAA)/ABA ratio was similar to the ratio of IAA/ABA.4. When the seed stored at low temperatures, the content of ABA increased steadily; the content of IAA was constantly changing at a low level; changes of the contents of both GA3 and ZR were similar to CK, however, the amplitudes were smaller. The ratio of GA/ABA was significant higher than CK and was increasing at first and then decreased which expressed large amplitude before and after 180 days. The ratio of IAA/ABA showed the maximum before and after 180 days, and then changed frequently. There was no regular pattern for the ratio of ZR/ABA. The ratio of (GA+IAA)/ABA was increased during 0～180 days and decreased during 180～270 days, then remained stable at a low level in the end.5. Seed of 4.2%≤MC≤6.4% retained higher germination percentage and seed vigor index at 5℃. Seed of MC=4.2% showed the best storage effect at 5℃. The germination percentage of seed of 5.3%≤MC≤6.4% was the highest, and the seed vigor index of MC=6.4% was higher than the seed of other MCs at -5℃. Seed of 5.3%≤MC≤7.5% showed the best storage effect at-5℃. The conductivity change of the seed stored at -5℃was similar with the seed stored at 5℃, while, the former amplitude was smaller.6. The contents of soluble sugar and starch decreased during the seed storage; and the content of soluble protein increased accompanied by the extension of storage time and the decline of MC. However, the content of crude fat showed no regular pattern and there was no significant difference among different treatments.7. The content of O2·- increased steadily during the storage, and this content in the mass decreased accompanied by the decline of MC; the content of MDA increased accompanied by the extension of storage time and the decline of MC, meanwhile, the amplitude increased accompanied by the rise in MC. At 5℃, the contents of both O2·- and MDA were the smallest with the seed of 5.3%≤MC≤6.4%. At -5℃, the content of O2·- with the seed of MC=4.2% was the smallest and the content of MDA with the seed of 4.2%≤MC≤6.4% was the smallest. The content of free proline of the seed stored at 5℃was smaller than the seed stored at -5℃.8. There were significant differences for the activities of both SOD and POD among different seed moisture contents during seed storage. The activity of SOD increased obviously in the ultradried seeds and the amplitude was increasing accompanied by the rise in MC. The activity of POD was increasing at first and then declined in the ultradried seeds.9. Accompanied with the extension of storage time, structure of albuminous cells was damaged. Ultradry and stored at low temperature could relieve consenescence of cells. The cytoplasm of seed of MC=3.3% became thick and the protoplast was degraded in some cells which left only overlapping cell walls by the end of seed storage.
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