Temperature dependency of T 1 of water protons in leaf tissues of chilling-sensitive crops was investigated by pulse nuclear magnetic resonance (NMR) spectroscopy. Arrhenius plots of the T 1 of tomato and cucumber leaves indicated biphasic with temperature drop from 20 to 0°C. "Breaks" in Arrheius plots of T 1 of fresh leaves in tomato and cucumber occurred at about 12.5°C and 10°C, respectively, while those of chilling-insensitive clone of gloxinia indicated no break point during the same process. Furthermore, thermal hysteresis of T 1 was observed during a slow cool-warm cycle in these crop leaves. The relation between the restoration process of T 1 upon warming and the degree of chilling injury is summarized as follows: 1) a slight prolongation of T 1 or no hysteresis was observed when chilling injury did not occur; 2) a marked prolongation of T 1 was observed when injury occurred; 3) a marked shortening of T 1 occurred from the earlier stage of the warming process when tissues were severely injured. In conclusion, Arrhenius plots of T 1in leaves provide a sensitive and non-invasive information for evaluating plant response to chilling stress in crops.
|Number of pages||7|
|Journal||Journal of the Faculty of Agriculture, Kyushu University|
|Publication status||Published - Oct 1 2002|
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science