Ca2+参与H2O2促进盐碱混合胁迫下燕麦种子的萌发和成苗

盐碱胁迫是制约作物高产优质的重要因素，Ca²⁺和H₂O₂作为信号分子参与作物逆境响应调节。为了解Ca²⁺是否参与H₂O₂对盐碱胁迫下植物种子萌发和成苗的调控，以燕麦（Avena nude）为试验材料，采用隶属函数分析方法，研究了胞外游离Ca²⁺螯合剂EGTA、质膜Ca²⁺通道阻断剂LaCl₃和液泡膜Ca²⁺释放抑制剂钌红（RR）与H₂O₂共处理对盐碱混合（NaCl：Na₂SO₄：NaHCO₃：Na₂CO₃=12：8：9：1）胁迫下种子萌发和成苗的影响。结果表明，25~200 mmol·L^-1盐碱混合胁迫显著抑制燕麦的种子萌发和成苗，抑制程度随浓度提高而增强；0.001~2 mmol·L^-1 H₂O₂能够促进燕麦种子的萌发和成苗，且0.5 mmol·L^-1 H₂O₂可以显著缓解75 mmol·L^-1盐碱混合胁迫对燕麦种子萌发和成苗的抑制作用；而EGTA、LaCl₃和RR均能消减H₂O₂对盐碱混合胁迫下燕麦种子萌发和成苗的促进作用。表明Ca²⁺参与H₂O₂促进盐碱混合胁迫下燕麦种子萌发和成苗的信号转导过程。

Effect of Ca2+ on Seed Germination and Seedling Formation of Oat Induced by H2O2 under Saline-Alkali Complex Stress

Salinity-alkalinity stress is an important factor of restricting crop high-yield and good quality, Ca²⁺ and H₂O₂ as signal molecules involved in crop response to stress. In order to understand whether Ca²⁺ is involved in the regulation of H₂O₂ on the seed germination and seedling formation in plant under saline-alkali stress, using subordinate function analysis method, we studied the effects of extracellular dissociation Ca²⁺ chelant EGTA, plasma membrane Ca²⁺ channel blockers LaCl₃, tonoplast Ca²⁺ release inhibitor ruthenium red(RR) and H₂O₂ on seed germination and seedling formation under saline-alkali complex stress(NaCl:Na₂SO₄:NaHCO₃:Na₂CO₃=12:8:9:1) with oat(Avena nude). The results showed that 25-200 mmol·L^-1 saline-alkali complex stress significantly inhibited seed germination and seedling formation of oat, and its inhibition was more obvious as the concentration was increased. While 0.001-2 mmol·L^-1 H₂O₂ could promote the seed germination and seedling formation of oat, and 0.5 mmol·L^-1 H₂O₂ significantly relieve the inhibition of 75 mmol·L^-1 saline-alkali complex stress to seed germination and seedling formation of oat. After EGAT treatment, combining with LaCl₃ and RR, the effect of H₂O₂ was decreased. Therefore, Ca²⁺ was involved in the signal transduction of seed germination and seedling formation of oat induced by H₂O₂ under saline-alkali mixed stress.