Diurnal variation of water potential of wheat under contrasting weather conditions

摘要

Abstract The diurnal variation of the water potential of wheat was measured with a pressure chamber. Flag leaf water potential decreased rapidly in the morning to low levels and did not recover until evening. On one day, ear water potential was higher than leaf water potential, particularly under irrigation, but still fell below —10 bars in the middle of the day. The results suggest that there is a high resistance to water uptake by plants.