盐碱胁迫对紫穗槐种子萌发的影响

摘要

以紫穗槐种子为材料,用不同浓度的NaCl、Na2SO4、NaHCO3和Na2CO3混合溶液对其进行胁迫处理,研究不同浓度盐碱胁迫对紫穗槐种子的发芽率、发芽势、发芽指数、活力指数的影响.结果表明,紫穗槐种子的各项萌发指标随着盐浓度和pH值的升高而逐渐降低.NaCl、Na2SO4、NaHCO3、Na2CO3按摩尔比1∶1∶0∶0混合,混合盐总浓度分别为15、30 mmol/L时,发芽率分别为62.12％、60.00％,略低于蒸馏水对照(63.33％)；上述4种盐按9∶1∶1∶9、1∶1∶1∶1混合,对应的混合盐总浓度为120、200 mmol/L时,发芽率分别仅为8.38％、7.33％；按9∶1∶1∶9混合,混合盐总浓度为200 mmol/L时,胁迫强度超出紫穗槐种子的忍受极限,所有萌发指标均为0.说明紫穗槐种子具有一定的耐盐碱性,盐碱胁迫抑制紫穗槐种子的萌发,其中高盐高pH值的抑制作用最大.盐胁迫和碱胁迫相互协同,共同影响紫穗槐种子的萌发.%Using Amorpha fruticosa seeds as materials,the effects of different concentration mixed solution of NaCl,Na2SO4,NaHCO3 and Na2CO3 on the seed germination rate,germinability,germination index,and vigor index were studied.The results showed that all the seed germination indexes decreased gradually with the increase of salt concentration and pH.The treatments of mixture of NaCl,Na2SO4,NaHCO3 and Na2CO3 (molar ratio=1 ∶ 1 ∶ 0 ∶ 0),with total salt concentration of 15 and 30 mmol/L,gave the germination rates of 62.12％ and 60.00％,respectively,slightly lower than the control (63.33％).When the four salts were mixed with molar ratio of 9 ∶1 ∶ 1 ∶ 9 and 1 ∶ 1 ∶ 1 ∶ 1,i.e.,the total salt concentration of 120 mmol/L and 200 mmol/L,the germination rates were only 8.38％ and 7.33％,respectively.When the molar ratio was 9 ∶ 1 ∶ 1 ∶ 9 (total salt concentration of 200 mmol/L),the stress intensity exceeded the endurance limit of Amorpha fruticosa seeds,with all the germination indexes of zero.The results indicated that Amorpha fruticosa seeds had a certain tolerance to saline-alkali stress,which inhibited the seed germination.Salt and alkali stress coordinated and mutually influenced the germination of Amorpha fruticosa seeds.