混合盐碱胁迫对羊草种子萌发的影响OA

In order to investigate the effects of mixed saline-alkali stress on seed germination of Leymus chinensis(L.chinensis),the experiment simulated saline-alkali stress environments using neutral salts(NaCl,Na2 SO4)and alkaline salts(NaHCO3,Na2 CO3)were mixed in molar ratios of 1∶9∶9∶1(mild[S],pH value=9.07),1∶1∶1∶1(moderate[M],pH value=9.70),and 9∶1∶1∶9(severe[L],pH value=10.24).Each treatment group included five concentration gradients(30,60,90,120,150 mmol/L),with purified water as the control(CK,pH value=6.90).The seeds of L.chinensis No.9 were subjected to saline-alkali stress,and germination indicators(germination rate,germination potential,germination index,vigor index),morphological indicators of seedlings(radicle length,plumule length)and salt damage rate were measured,and a two-way analysis of variance was conducted on the seed germination of L.chinensis to examine the effects of salt concentration,pH value,and their interaction.The suitable mixed salt concentration range,half-lethal concentration,and limit concentration of L.chinensis seeds germination were calculated.The results showed that low salt concentration(30 mmol/L)and mild(pH value=9.07)mixed saline-alkali stress had no significant effect on the germination of L.chinensis seeds.However,as the salt concentration and pH increased,the inhibitory effect on the germination of L.chinensis seeds gradually intensified.When the salt concentration reached 150 mmol/L and under severe(pH=10.24)mixed saline-alkali stress,L.chinensis seeds could hardly germinate.When the pH value was 10.24,the suitable salt concentration of L.chinensis seed germination was only 37.95 mmol/L.It was found that salt concentration,pH value and their interaction all significantly inhibited the germination of L.chinensis seeds,among which pH value was the decisive influencing factor,followed by salt concentration.It indicated that in the mixed saline-alkali environment,the alkaline factor(pH value)played a dominant role in inhibiting the seed germination of L.chinensis.