Sensitivity of stem diameter variations for detecting water stress in tomato transplants.

摘要

The effect of water stress on the stem diameter and derived parameters was studied in tomato transplants (cv. Pannovy) under greenhouse conditions in Geisenheim, Germany. Under 2 irrigation levels, 50 hPa (well irrigated control) and 500 hPa (water stress), a significant decrease in daily maximum stem diameter and accumulative stem diameter growth rate was observed. Maximum daily shrinkage increased significantly in the water stress transplants comparing to the control. Solar radiation affected positively stem growth rate and stem shrinkage in sunny days. In general, acquiring stem diameter derived indices measured by linear variable displacement transducer is a sensitive method to detect plant water status under water stress conditions.