Effects of Stronium Stress on the Antioxidative System ofSoybean (Glycine max)

Purpose In order to study the effect of strontium on soybean antioxidant system.

Method The soybean seedlings of Vc period were deal with using different concentration (0.00, 1.00, 5.00, 10.00, 20.00 and 40.00 mmol/L) SrCl₂ with 1/2-strength Hoagland nutrient solution. The effects on the growth, enzyme activities and isoenzymes of POD, SOD and CAT were analyzed by different treatments until soybean grow to V2 period.

Result The growth of soybean was significantly inhibited by SrCl₂ treatments (P<0.05). The inhibition of soybean growth was greater with increasing SrCl₂ concentration. The POD activity rapidly increased from 0.00 to 10.00 mmol/L SrCl₂ concentrations and decreased with increasing of SrCl₂ concentration when SrCl₂ concentration exceeded 10.00 mmol/L. Activities of SOD and CAT of addition SrCl₂ treatment were significantly higher than no addition (P<0.05). Two enzyme activities were the highest 5.00 mmol/L SrCl₂ concentration. The activities decreased with increasing SrCl₂ concentration when SrCl₂ concentration exceeded 5.00 mmol/L. The ratio of SOD/POD, SOD/CAT and SOD/(POD+CAT) were significantly diminished in addition SrCl₂ treatment (P<0.05). There was one new band of POD isoenzyme in 1.00 and 5.00 mmol/L SrCl₂ treatments. The bands of POD isenozyme were reduced more than 5.00 mmol/L SrCl₂ concentrations. There was one new band of SOD and CAT isenozyme in SrCl₂ treatments, respectively.

Conclusion The activities of soybean antioxidative enzyme were enhanced to alleviate the stronium stress in SrCl₂ treatment. It is limiting factor of alleviation stress that SOD activity enhanced relatively low. SrCl₂ treatment could affect the expression of antioxidant isoenzymes.