Effect of different water conditions on Panax notoginseng seeds after-ripening and germination physiology

Effect of different water conditions on the physiological indexes (e.g.seed water content, vigor, antioxidase activities)of Panax notoginseng seeds were studied under process of after-ripening and germination.The results showed show that compared with 2.5% treatment, under the treatment of 5%, P.notoginseng seeds possessed stable seed water content, the seed vigor was exceed by 51%,variation of antioxidant enzyme (SOD, POD, CAT) activity and malondialdehyde (MDA) content were small, crude fat and total sugar content decreased significantly.With the increase of PEG 6000 concentration, the germination characteristic indexes obviously decreased, antioxidase activities increased firstly and decreased afterwards, content of MDA, soluble protein and total sugar increased obviously.There were significant positive correlation between germination characteristic indexes and osmotic substance content(r0.900, P0.01), and significant negative correlation with MDA (r0.900, P0.01).In conclusion, because the characteristic of dehydration intolerance of P.notoginseng seeds, 5% water content of sand burying stratification treatment was the best for after-ripening, 15% concentration of PEG 6000 treatment was the highest tolerance limit of germination process.