Crop Timing Using Thermal Units and Growing Media Moisture Tension Progress Report — August 1995
Date 9/1/95
Title of Project Crop Timing Using Thermal Units and Growing Media Moisture Tension
Institution where work is being conducted Ohio State University
Amount of Endowment Grant $6,000
Covering Period 1/95 to 12/95
Anticipated Date of Completion/Final Report 12/95
Individual(s) Conducting Project:
(List Project Leader First)
Dr. Claudio C. Pasian - Title Assistant Professor
Telephone Number
Dr. R. Peter Fynn - Title Assistant Professor
Dr. Mark Rose -Title Research Scientist in Floriculture
Crop Timing Using Thermal Units and Growing Media Moisture Tension
Claudio Pasian, R. Peter Fynn, and Mark Rose
Ohio State University
- Work on this research began immediately following the agreement reached between TheOhio State University Foundation and The American Flower Endowment regarding the contract
to be signed by both institutions. The lengthy negotiations set us behind schedule.
- We have made substantial progress nonetheless setting up and launching the experimentsnow in progress. Plants of two minirose cultivars, ‘Candy Sunblaze’ and ‘Red Sunblaze’ have
been propagated and are being used in the tests.
- Our team has developed and assembled all irrigation system to water three groups ofplants based on their three different soil water tensions. We tested the system by determining the
coefficient of uniformity of the emitters. The difference in water delivered by each emitter has
been determined to be 20% or less.
- The irrigation water is controlled by tbree tensionmeters so that three groups of plants arebeing grown under three soil water tensions: high, low, and intermediate. Elements for the
construction of a second, more sophisticated, tensionmeter-based irrigation system have been
purchased and the system is under assembly. This new system allows for the computerized
control and measurement of the irrigation as well as computerized storage of the variables such
as water, tension, temperature and light.
- Observations of rose plant development as a function of temperature for both rosecultivars are being analyzed to determine base temperature which in turn will be used in the
calculation of thermal Units (Degree Day). Thermal units will allow us to replace the variable
time when plants will be grown at similar soil water tensions but different air temperatures (i.e.
different seasons).
- Considering the delay in starting this research, we have made significant progress. Weanticipate that meaningful results will be presented in the next progress reports.
