Abstract
The physiological changes in intact mume (Prunus mume Sieb. et Zucc.) seed were compared to fig (Ficus carica L.) drupelet which develop parthenocarpically with bearing seedless tissues by using ^1H-NMR spectroscopy. Water compartments shown as Lorentzian/Gaussian curves indicated that the mobile water components decreased in mume seeds inversely to that of fig drupelet during maturation. The high mobility of water in the immature mume seeds decreased with their development instead of diminished free water; consequently, oil accumulated. In contrast, free water in the fig drupelet tissues markedly increased with their development accompanying with sugar accumulation. Water in the tissues is present in several compartments, each showing different water molecule mobilities. Long component of the NMR relaxation times (T_1, T_2) derived from vacuolar water in mature seeds of mume fruit markedly decreased with lowering of water content while fig drupelet water ranging about 90% per fresh weight basis did not indicate obvious relationship to T_1 or T_2 compared to the seed. Thus, the water status is considered to reflect physiological changes such as that regarding cellular heterogeneity. The analysis of the water compartments, Lorentzian/Gaussian curve, provides a new concept of seed dehydration indicating contradictory water status in seedless tissues with maturation.
