南京林业大学学报（自然科学版）2025，Vol.49Issue(3)：144-152,9.DOI:10.12302/j.issn.1000-2006.202311009
娜塔栎种子失水过程中的生理响应
Physiological response of Quercus texana seeds during dehydration
摘要
Abstract
[Objective]Quercus texana is primarily propagated via seeds,but these are highly sensitive to dehydration,which limits their transport and storage potential.This study investigated the physiological changes occurring during seed desiccation to elucidate the mechanisms underlying their intolerance to dehydration.[Method]Seeds of Q.texana were analyzed at moisture contents(WC)of 39.6％(fresh seeds),35.0％,30.0％,25.0％,20.0％,15.0％,and 13.0％.Germination percentages and physiological parameters,including superoxide dismutase(SOD),catalase(CAT),proline,saccharides,soluble proteins,and malondialdehyde(MDA),were measured to explore the effects of desiccation.[Result]When the WC exceeded 25.0％,the germination percentage remained above 90.0％.However,as the dehydration of Q.texana seeds progressed,the germination percentage progressively declined,reaching 38.3％at a WC of 15.0％.Further reduction in WC to 13.0％resulted in the complete inhibition of germination,with the percentage falling to 0.0％.The regression model(y=0.016 5x3-1.553 6x2+47.84x-392.03)established critical and semilethal WC at 21.4％and 16.7％,respectively.MDA levels increased continuously during desiccation,indicating heightened lipid peroxidation.SOD content exhibited an initial rise,followed by a sharp decline at 25.0％WC,while CAT activity exhibited a consistent decline,accelerating below 25.0％WC.The levels of osmoregulatory substances,such as proline and sucrose,increased up to 20.0％WC but decreased thereafter.The soluble sugars peaked at 15.0％WC,while reducing sugars steadily increased.The soluble protein content declined,though this decline was not statistically significant across desiccation stages.Correlation analysis revealed a significant positive relationship between germination percentage and SOD and CAT activities,and a negative relationship with MDA,reducing sugar,proline,soluble sugar,and sucrose levels.[Conclusion]Q.texana seeds demonstrated a high level of intolerance to dehydration,necessitating a minimum WC of 21.4％,preferably above 16.7％,for safe transport and storage.It was observed that initial dehydration stress is mitigated by enhanced SOD activity and increased osmoregulatory substances such as proline,sucrose,and soluble sugars.However,the progressive decline in CAT activity and soluble proteins,combined with MDA accumulation and rising reducing sugars,compromises seed viability under prolonged desiccation.关键词
娜塔栎/顽拗性种子/脱水耐性/渗透调节物质/抗氧化酶Key words
Quercus texana/recalcitrant seeds/dehydration tolerance/osmoregulator/antioxidant enzyme分类
农业科技引用本文复制引用
赵薇,王浩宇,朱铭玮,徐志标,黄涛,孙李勇,侯静,李淑娴..娜塔栎种子失水过程中的生理响应[J].南京林业大学学报（自然科学版）,2025,49(3):144-152,9.基金项目
江苏省林业科技创新与推广项目(LYKJ[2019]38). （LYKJ[2019]38）
