The Effect of Potassium Deficiency on Stomatal and Cuticular Resistance in Tea (Camellia sinensis)

The effect of potassium deficiency on cuticular resistance and diurnal variation in stomatal diffusive resistance was studied in tea (Camellia sinensis). The plants were grown in sand and potassium deficiency induced by withholding the supply of potassium. The results showed that during the day potassium-deficient leaves had a higher stomatal diffusive resistance than control leaves. However when solar radiation was reduced by clouds the stomatal diffusive resistance in both control and potassium-deficient leaves was not significantly different. Night opening of stomata was observed in both control and potassium-deficient leaves, but noticeably lower in the latter. Potassium-deficient leaves had a lower cuticular resistance than control leaves.