胀果甘草种子萌发对干旱胁迫的生理响应

Physiological and biochemical responses to drought stress during seed germination of Glycyrrhiza inflata

为探讨胀果甘草种子萌发对干旱胁迫的生理生化适应机制,以聚乙二醇(PEG)-6000模拟干旱胁迫,分析了胀果甘草(Glycyrrhiza inflata)种子萌发过程中发芽率(GR)、丙二醛(MDA)及游离脯氨酸(Pro)、可溶性糖(SS)含量和超氧化物歧化酶(SOD)、过氧化物酶(POD)活性的动态变化规律。结果显示,水势为-0.1MPa时,GR达到100%,之后随着干旱胁迫增强而显著降低(P<0.05);MDA、Pro含量及SOD、POD活性都表现出水势≥-0.2MPa时增加和-1.4MPa≤水势<-0.2MPa时减少的明显趋势(P<0.05),这4个指标两两之间的相关关系均达到显著水平(P<0.05);而干旱胁迫增强使SS含量显著增加(P<0.05)。

Dynamics of germination rate（GR）,malondialdehyde（MDA）,free proline（Pro）,soluble sugar（SS）,superoxide dismutase（SOD） and peroxidase（POD） were analyzed during seed germination of Glycyrrhiza inflata under drought stress simulated by polyethylene glycol（PEG）-6000.The Results showed that,GR was 100% under-0.1MPa of water potential then decreased when the drought stress intensified;MDA,Pro,SOD and POD increased when water potential≥-0.2MPa but then decreased when-1.4MPa ≤water potential〈 -0.2MPa（P〈0.05）.The correlations among the aforementioned four indexes were significant（P〈0.05）,while the drought stress increased SS significantly at P〈0.05.