?A SENSOR FOR MONITORING WATER UPTAKE BY A SIMULATED PLANT ROOT
Keywords:
Optoelectronic device, Plant root, Transducer, Meniscus, Irrigation.Abstract
An optoelectronic device for measuring very slow rates of flow through a simulated plant root was designed,
constructed and tested in the laboratory of Agricultural Engineering Department, University of Newcastle upon
Tyne, England, during the period from 1985through 1987. 'Transducers' were used to monitor the advance rate of
meniscus through a capillary glass tube. The transducers consisted of a small piece of plastic (Tufnol), a 6 mm
filament bulb and a phototransistor unit.The time recordedby each transducer was printed out in a microprinter.The
optoelectronic device reported in this paper can be used in the monitoring of soil water extraction by a physically
simulated plant root which would ultimately allow plant water stress to be used directly in the control of irrigation.
