DYNAMIC STATES OF WATER MOLECULES AND SUGARS IN HORTICULTURAL PLANTS IN RESPONDING ENVIRONMENTAL STRESSES USING NMR SPECTROSCOPY

核磁共振氢谱是一种非破坏性的方法，可以用来研究水在体内的动态。本研究利用核磁共振氢谱(MRI)、核磁共振氢谱显微镜和高分辨核磁共振波谱技术，研究了低温处理、果实成熟和种子萌发过程中鳞茎的质子密度图、糖的分布和松弛时间(T1、T2)。在此基础上，用组织化学方法对影响水分状态变化的因素进行了讨论：1)郁金香鳞片经低温处理后，鳞片薄壁组织中流动水的信号强度增强，而非冷却鳞片中没有观察到流动水。随后，当转移到环境温度时，预冷灯泡中更高的呼吸产生更高的水产量，从而促进新陈代谢活动。2)萌发大麦种子中的糖主要分布在维管束和溶解胚乳中。糖主要通过维管束运输，同时迅速结合到叶片的叶肉细胞中。3)无花果和日本杏果实组织中的水分由三种水分成分组成，自由水是主要成分，随着果实的成熟，水分吸收显著。水室反映了果实组织中细胞的异质性。此外，樱桃果实的水分状况与果实成熟时种子和果皮的水分状况是矛盾的。

^1H-NMR is a non-destructive method that can be used to study the dynamic states of water in vivo. In this study, proton density map, distribution of sugars and relaxation times (T_1, T_2) in bulbs exposed to low temperatures, fruit with ripening and seed germination were examined by using ^1H-NMR imaging (MRI) , ^1H-NMR microscopy and high resolution ^1H-, ^<13>C-NMR spectroscopy. On the basis of the results, factors on changes of water status were also discussed in relation to cellular components by histohemical methods.1) Low temperature treatments in tulip bulbs increased signal intensity of mobile water in the scale parenchyma tissue whereas no mobile water was observed in noncooled bulb scales. In succession, higher water production resulting from higher respiration in the precooled bulbs when transferred to ambient temperatures encouraged metabolicactivity. The synergistic effects in water status would lead to rapid growth of the flower stalk after planting.2) Sugars in germinating barley seeds were located in vascular bundle and the solubilized endosperm. The sugars are primarily transported through the vascular bundles and, at the same time, rapidly incorporated into mesophyll cells in the leaves.3) Water in fig fruit and Japanese apricot fruit tissues consisted of three water components and free water appeared as major fraction with significant water uptake with fruit ripening. Water compartments reflected cellular heterogeneity in the fruit tissues. Furthermore, water status in cherry fruit was contradictory between the seed and pericarp with fruit ripening.