| 摘要: |
| 【目的】研究外源甜菜碱对盐胁迫下千屈菜种子萌发及幼苗生长的影响,为盐碱地区千屈菜大规模优质高产种植提供参考。【方法】以千屈菜种子为试验材料，将消毒并浸泡24 h的千屈菜种子随机分成6组，每组50粒，整齐排列在直径为12 cm、垫有2层滤纸的培养皿中，其中1组用移液器添加蒸馏水20 mL,记为CK1处理；另外5组先添加10 g/L NaCl 10 mL，再分别添加0，1，3，5，7 g/L外源甜菜碱10 mL，依次记为CK2、T1、T2、T3和T4处理，置于25 ℃温室培养，统计种子发芽指标。再选取株高10～15 cm、生长状况基本一致的千屈菜幼苗进行盆栽试验，设CK1、CK2、T1、T2、T3和T4 6个处理，其中CK1处理不添加任何药品，进行蒸馏水正常培养；CK2处理先用10 g/L NaCl 10 mL进行浇灌，再叶面喷施蒸馏水10 mL；T1、T2、T3和T4处理均先用10 g/L NaCl 10 mL进行浇灌，再分别用1，3，5，7 g/L外源甜菜碱10 mL喷洒于叶片上，隔天喷洒1次，处理7 d后随机选取千屈菜幼苗，测定其生长指标及叶片中叶绿素、保护酶（SOD、POD和CAT）活性及MDA和可溶性蛋白含量。【结果】在NaCl胁迫下，外源甜菜碱能使千屈菜种子萌发指标升高，幼苗生长指标、叶绿素含量和保护酶活性增强，可溶性蛋白含量增加且维持在正常水平，从而缓解盐胁迫对千屈菜植株生长发育的抑制程度及危害；随外源甜菜碱质量浓度升高，各指标均呈现先升后降的变化趋势，且甜菜碱质量浓度为5 g/L时，其对千屈菜种子的萌发率，幼苗的根长、株高、鲜质量和干质量及叶片总叶绿素含量，POD、SOD、CAT活性，MDA含量的改善效果最为显著，较CK2处理分别增加了96.50％，49.35%，22.60%，61.67%，52.01%，300.73％，156.72%，191.67%，99.43%，57.69%；甜菜碱质量浓度为3 g/L时，盐胁迫下千屈菜幼苗可溶性蛋白含量最高，较CK2处理增加了628.66%。【结论】喷施5 g/L的外源甜菜碱可增强千屈菜种子及幼苗的耐盐性。 |
| 关键词: 千屈菜 甜菜碱 盐胁迫 种子萌发 幼苗生长 逆境生理 |
| DOI： |
| 分类号: |
| 基金项目:陕西省科技厅重点研发计划项目（2021NY-066）；中央引导地方科技发展专项（2019ZY-FP-02） |
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| Effects of exogenous glycine betaine on Lythrum salicaria seed germination and seedling growth under salt stress |
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HUA Zhirui
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| Abstract: |
| 【Objective】This study investigated the effects of exogenous betaine on seed germination and seedling growth of Lythrum salicaria under salt stress to provide reference for large-scale high-quality and high yield planting of Lythrum salicaria in saline alkali area.【Method】The seeds and seedlings of Lythrum salicaria were arranged neatly in a petri dish with a diameter of 12 cm and two layers of filter paper.The seeds were randomly divided into 6 groups with 50 seeds in each group.The first group was added 20 mL of distilled water with pipette,denoted as CK1.The other 5 groups were added 10 mL of 10 g/L NaCl with pipette,and then 10 mL of exogenous betaine was added at concentrations of 0,1,3,5 and 7 g/L as treatments of CK2,T1,T2,T3 and T4,respectively.All treatments were cultured at 25 ℃ with 10 mL distilled water added every day to prevent drought,and germination number was counted.A total of 6 groups were treated for seedlings at heights of 10-15 cm with 3 pots in each group and 6 plants in each pot.CK1 was cultured with distilled water without any drugs.CK2 treatment was irrigated with 10 g/L NaCl 10 mL,followed by 10 mL distilled water.T1,T2,T3 and T4 were irrigated with 10 g/L NaCl 10 mL,and then sprayed with 10 mL exogenous betaine at concentrations of 1,3,5 and 7 g/L on leaves,once every other day.After 7 days,the growth indexes,contents of chlorophyll,soluble protein and MDA and activities of SOD,POD and CAT were measured.【Result】Under NaCl stress,exogenous betaine promoted willow vegetable seed germination rate,seedling anti-oxidation ability,enhance photosynthesis,and soluble protein content,so as to relieve inhibition and harm of salt stress on plant growth and development.With increase of exogenous betaine concentration,all indicators showed the trend of first increase and then decrease.When betaine concentration was 5 g/L,seed germination rate,root length,plant height,fresh weight,dry weight,chlorophyll content,POD,SOD and CAT activities,MDA content of seedling leaves had the most significant effects with increases of 96.50%,49.35%,22.60% and 61.67%,52.01%,300.73%,156.72%,191.67%,99.43% and 57.69% in comparison with CK2.The soluble protein content reached the highest when betaine mass concentration was 3 g/L with the increase rate of 628.66% in comparison with CK2.【Conclusion】Spraying 5 g/L exogenous betaine can enhance salt tolerance of seeds and seedlings of lythylandine. |
| Key words: Lythrum salicaria exogenous betaine NaCl stress seed germination seedling growth stress physiology |
