The Physiological And Biochemical Response To Artificial Aging Of Artemisia Sphaerocephala Seeds

The seeds of desert plant may experience longer natural aging process before meeting the appropriate conditions for germination, so to study the mechanism of seeds aging is important for the propagation and establishment to desert plants.This study was conducted to evaluate the response of Artemisia sphaerocephala which is the typical desert plants and Brassica campestris seeds under accelerated aging process.The accelerated aging test was carried 45 ℃ and a relative humidity of 100% with four duration periods of 24, 48, 72, 96 h. The main results are as follows:(1) Under the same aging treatment, the membrane of Artemisia sphaerocephala seeds integrity is better, with higher vigor and germination rate, it indicated that ageing resistance of Artemisia sphaerocephala seeds is stronger than Brassica campestris seeds.(2) The ROS content of sphaerocephala seeds is less than Brassica campestris seeds with the same treatment and sphaerocephala seeds face lighter oxidative stress.(3) The lipase activity and lipoxygenase activity of Artemisia sphaerocephala seeds are weaker than Brassica campestris seeds under each treatment, so the lipid oxidation and decomposition reactions are slower.The accumulation of malonaldehyde and free fatty acids are less, so caused minor damage to sphaerocephala seeds, it is main factors of sphaerocephala seeds maintain higher vigor under the same aging treatment.(4) After long time aging treatment, SOD, CAT, POD, APX and GR activity play an important role in maintain higher vigor of Artemisia sphaerocephala seeds by effectively keeping the oxygen balance.(5) High content of flavonoid and α- tocopherol are two of the main reasons sphaerocephala maintain high seed vigor by eliminating free radicals in aged sphaerocephala seed and reducing oxidative stress faced by seeds.