Abstract:
Hydrogen sulfide(H
2S)signaling plays an important role in seed germination and stress response.To explore the influence of soaking seeds with sodium hydrosulfide(NaHS,a donor of H
2S)on the seed germination of crops under saline-alkali stress,naked oat(Avena nude)seeds were selected as experimental material which were soaked with different concentration(0,50,100,200 and 400μmol·L
-1)of NaHS for 8 h,and then germinated in different concentrations of mixed saline-alkaline(the mole ratio of NaCl∶Na
2SO
4∶Na
2CO
3∶NaHCO
3is 12∶8∶1∶9)solution(0,15,30,45 and 60 mmol·L
-1)in petri dishes in incubator.Changes in germination percentage(Gp),germination index(Gi),vigor index(Vi),mean germination time(MGT),dry weight of seedlings(SDW)and comprehensive evaluation value of membership function(D)were analyzed.The effects of different concentrations of saline-alkali and NaHS and their interaction on Gp,Gi,Vi,MGT,SDW and D were significant(P<0.05)or extremely significant(P<0.01).The Gp,Gi,Vi,MGT,SDW and D decreased significantly with the increase of saline-alkali concentration.Compared with 0μmol·L
-1NaHS(CK),50 and100μmol·L
-1NaHS increased the Gp,Gi,Vi and D under 0 mmol·L
-1saline-alkali stress to different degrees.The 50μmol·L
-1NaHS significantly increased the Gp under 30 mmol·L
-1saline-alkali stress.The 50 and 100μmol·L
-1NaHS increased Gi under 15,30 and 45 mmol·L
-1saline-alkali stress to different degrees.The 50μmol·L
-1NaHS significantly increased Vi under 30 mmol·L
-1saline-alkali stress.The 50 and 100μmol·L
-1NaHS significantly increased D under 45 mmol·L
-1saline-alkali stress.However,the germination index values of other treatments were not significantly different or significantly reduced.These results suggest that soaking the seed with NaHS of appropriate concentration could relieve the inhibition of saline-alkali stress on seed germination of naked oats,optimal effects were reached at NaHS concentrations of 50μmol·L
-1under saline-alkali stress at below 45 mmol·L
-1,200 and 400 mmol·L
-1NaHS aggravated the inhibition of salinityalkali stress on seed germination,and NaHS had no palliative effect on the inhibition of seed germination of naked oat under high concentration of salinity-alkali stress(60 mmol·L
-1).