Physiological and biochemical characteristics of Apocynum venetum seeds in theprocess of artificial aging

Apocynum venetum, mainly distributing in the salinization and sandy area, is droughtcold tolerance and alkaliwind tolerance, and is suitable for various climate and soil. The response of seed vigor of A. venetum to harsh environments greatly affects the adaption of its population. Therefore, the objective of this study is to understand the physiological and biochemical characteristics of A. venetum seed in the process of artificial aging for verifying the rule of seed deterioration, disperse mechanism of population, and seed storage characters and longevity. An experiment was conducted to test the seed physiological characteristics of A. venetum under the conditions of relative humidity of 100% and 35 ℃ and 50 ℃ for 84 h. The results of this experiment showed that the seed electronic conductivity decreased in the initial stage and then increased in the late stage, and the activity of POD and SOD decreased gradually, whereas laching of soluble sugar increased under the same aging temperature as the aging time increased. The aging condition with high temperature impacted seed more greatly than that with low temperature. A. venetum seed responded to stress resistance with high temperature and was heatresistance.