饥饿胁迫下龙眼果实脱落与果实不同组织能荷变化的关系

Exploration of the Relationship Between Longan Fruit Abscission In-duced by Starvation Stress and Changes in Energy Charge of Differ-ent Fruit Tissues

在龙眼果实发育过程中因碳水化合物供应不足而频繁发生采前落果。碳水化合物的代谢与能量代谢密切相关,而能荷的变化涉及到呼吸及碳水化合物消耗,是衡量果实生理机能的重要指标。为了揭示龙眼果实非正常脱落与能荷的关系,本研究以储良龙眼发育后期(花后80 d)果实为材料,采用果穗环剥处理阻断碳水化合物供应人为制造饥饿胁迫,可导致5 d内果实完全脱落。在此过程中,本研究分析了果实脱落过程中各组织ATP、ADP和AMP含量及能荷水平的变化。结果表明:果实各组织能荷值表现为种子>果皮>果肉,而伴随着饥饿胁迫加剧,果实脱落进程中,整个试验过程,ATP显著降低,AMP显著上升,各组织的能荷值呈现下降趋势,但种子能荷值降幅最小,种子是能荷最稳定的器官。这些结果表明,饥饿胁迫可导致果实能量水平降低,但是不同组织能量变化幅度不同,种子可维持相对稳定的能荷水平,暗示饥饿胁迫下,果实的资源优先供应种子,进而维持其能量状态。

Frequent pre-harvest fruit abscission occurs during the development of longan fruits due to insufficient carbohydrate supply.The metabolism of carbohydrates is closely related to energy metabolism,and changes in energy charge related respiration and carbohydrate consumption,which are important indicators for measuring fruit physiological functions.In order to reveal the relationship between abnormal abscission and energy charge of longan fruits,this study used the fruits of the late stage of development(80 days after flowering)of“Chu Liang”longan as the materials,and used ear girdling plus defoliation treatment to block carbohydrate supply and artificially create hunger stress,which can lead to complete fruit abscission within 5 days.During this process,this study analyzed the changes in ATP,ADP,and AMP contents and energy charge levels in different tissues during fruit abscission.The results showed that the energy charge values of different tissues in the fruit were as follows:seeds>fruit skin>fruit flesh,and with the intensifi-cation of starvation stress,during the fruit abscission process,ATP significantly decreased and AMP significantly increased throughout the experiment.The energy charge values of different tissues showed a downward trend,but the decrease in seed energy charge value was the smallest,and the seed was the organ with the most stable energy charge.The results indicated that starvation stress could lead to a decrease in fruit energy levels,but the magnitude of energy changes varied among different tissues,seeds could maintain relatively stable energy charge levels,suggesting that under starvation stress,fruit resources prioritized the supply of seeds,thereby maintaining the energy state.