摘要
以苗龄2年的黑壳楠实生苗为试验材料,设置4个低温梯度(4、0、-4和-6℃)处理,并以常规温度(25℃)培养为对照,分析其在不同温度胁迫下的生长状态和生理指标的变化,以期探析黑壳楠的低温响应机制,为黑壳楠开发利用提供参考。结果表明:随处理温度的降低,除4和0℃处理外,黑壳楠幼苗出现不同程度的水渍化。低温胁迫后,SOD与POD活性显著上升,在4℃时达到峰值。可溶性蛋白与脯氨酸含量呈先上升后下降的趋势,可溶性糖含量与它们的变化趋势相反,丙二醛含量在-6℃处理时较对照(25℃)显著上升。随处理温度的降低,叶绿素荧光参数最大光化学效率(F_(v)/F_(m))和光系统整体综合性能指数(PI_(total))逐渐下降,4℃处理时TR_(o)/RC、φ_(R_(o))和ET_(o)/RC最高。黑壳楠能够抵抗4℃低温胁迫,且主要通过开启光合系统保护机制减少光抑制以及调节渗透物质含量、增强抗氧化酶活性等生理机制来减轻低温胁迫造成的伤害。
This study aimed to elucidate the mechanisms by which Lindera megaphylla responds to low-temperature stress,and provide reference for the cultivation and utilization of this plant species.Two-year-old seedlings of L.megaphylla were subjected to a range of low-temperature stress conditions,with temperatures varying from 25℃(control group)down to-6℃.The changes of physiological indexes such as osmotic regulators,antioxidant enzyme and chlorophyll fluorescence parameters activities under different stress were determined.The results indicated that as the stress temperature decreased,the seedlings exhibited signs of watery stains,except for those at 4 and 0℃.The activities of SOD and POD increased significantly,and reached a peak at 4℃.The contents of soluble protein and proline increased first and then decreased,contrary to the change of soluble sugar content,and the content of malondialdehyde increased significantly at-6℃ than that of control.The maximum photochemical efficiency(F_(v)/F_(m))and total performance index(PI_(total))decreased gradually with the decrease of treatment temperature.However,TR_(o)/RC,φ_(R_(o)) and ET_( o)/RC were the highest at 4℃ treatment.These results suggest that L.megaphylla can activate protective mechanisms within its photosynthetic system to mitigate photoinhibition.The adverse effects of low-temperature stress can be lessened through physiological adaptations,such as modulating the content of osmotic substances,enhancing the activity of antioxidant enzymes,and increasing heat dissipation.
作者
陈云
张新
刘静
陈鹏
李永华
刘红利
CHEN Yun;ZHANG Xin;LIU Jing;CHEN Peng;LI Yonghua;LIU Hongli(College of Landscape Architecture and Art,Henan Agricultural University,Zhengzhou 450002,China;College of Food Science and Technology,Henan Agricultural University,Zhengzhou 450002,China)
出处
《植物生理学报》
CSCD
北大核心
2024年第12期1759-1768,共10页
Plant Physiology Journal
基金
国家自然科学基金(32201615)
河南省科技攻关项目(23210211106)
河南省科技兴林计划(YLK202211)。
关键词
黑壳楠
低温
酶活性
叶绿素荧光
Lindera megaphylla
low temperature stress
enzyme activity
chlorophyll fluorescence
