Year: 1996
Type: dissertation
Abstract: Sap pressure of cut tomato stems was monitored using a real-time (strict time constraint) data acquisition system to access changes in the root zone environment.Hydroponically grown tomato plants were cut, and a gas-free connection was made to a temperature-compensated pressure transducer.When plants were bathed in nutrient solution under isothermal conditions, pressure increased to a maximum within 10 to 75 minutes; maxima varied in the range of 20 kPa to 150 kPa.A fatigue phenomenon occurred with all plants, exhibited by decreases in pressure maxima over time as pressure cycles were repeated.When root zone aeration was stopped or a nitrogen atmosphere was used, pressure dropped following a lag of about 30 minutes.This decrease in pressure was partially reversible when aeration was resupplied.Near instantaneous changes in sap pressure occurred when the root zone was manipulated by imposing a temperature v gradient or by increasing the osmotic potential of the solution.The technique reported may be useful for determination of the role of changing root zone environments on sap flux and perhaps for assessment of the health status of plants.
DOI: 10.7275/20483018
Author: Yao, Fude
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W3136616742