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NCR-101 Activities

Measurement and Reporting Guidelines | Baseline Growth Studies
Growth Chamber Manuals | Instrument Package

In addition to its regular meetings, the NCR-101 committee has developed activities to provide information to aid all controlled environment researchers. Some of these activities are highlighted below.

Measurement and Reporting Guidelines
These guidelines provide recommendations on what should be measured, units to utilize, where to measure, when to measure, and what to report in research articles. These guidelines have been published in many different plant science journals and are kept updated through publication in the Engineering Practice publication of the American Society of Agricultural Engineers (2004), and also detailed in Biotronics by Tibbitts,Sager & Krizek (2000). Interaction with controlled environment groups in the United Kingdom, Australia and New Zealand has led to the development of internationally accepted guidelines for conducting growth chamber research (ICCEG 2004) and also for the conduct of tissue culture research (ICCEG 2008). A detailed discussion of the development of these guidelines can be found in a history of the growth chamber committees by Tibbitts & Krizek, 1997. For copies of the guidelines proceed to the Guidelines Webpage.

Baseline Growth Studies
An early effort of the committee was the determination of growing procedures and necessary environmental measurement to obtain optimum and repeatable growth rates in studies conducted in the same and different laboratories. This became a very difficult task and required nearly 5 years to develop repeatable procedures and obtain baseline growth rates for lettuce (Hammer et al, 1978) and marigolds (Ormrod et al, 1980). In the course of this effort it was found necessary to utilize a common set of instruments to obtain consistent environmental measurement. Instruments were obtained through a National Science Foundation grant and distributed among the co-operating laboratories. Also seed, media, and containers were obtained and distributed to the committee members. Considerable effort was also put on the development of repeatable hydroponic culture procedures (Tibbitts et al., 1978) although no plant growth studies were reported on this work. More details of these studies can be found in the committee history (Tibbitts & Krizek, 1997).

Growth Chamber Manuals
The members of the committee and other interested individuals contributed to a publication in 1978 of a procedures manual Langhans, (1978) that was directed toward helping new growth chamber users grow plants effectively. This was totally rewritten and expanded in another procedures manual in 1996, Langhans & Tibbitts, (1996), with chapters on Light, Temperature, Humidity, Carbon Dioxide, Air Movement, Air Contaminants, Physiological Disorders, Pests & Diseases, Plant Culture in Solid Media & Hydroponics, Experimental Design, Chamber Specifications, Special Use Chambers, Measurement & Reporting Guidelines, and Crop Growth Requirements. This 1996 publication is available for order by mail or for viewing in PDF format on this web site:
• Langhans & Tibbitts, (1996) [Order Book] [View PDF files]

Controlled Environment Instruments
A considerable amount of the committee's efforts have been directed toward ensuring accurate and effective measurement of the environment to which the plant is exposed during its growth in the chamber.

Standardized Instrument Package: A package of instruments obtained through a grant from NSF funds has been maintained and continuously updated as new instrumentation has become available. Of particular interest and emphasis has been the accurate measurement of radiation in the chambers, including the photosynthetic wavelengths, long wave intensity, and most recently ultraviolet wavelengths. This instrument package is maintained by one laboratory with regular auditing of the instruments and is forwarded to anyone requesting it for a 2 week period of use with payment of a fee of $300 that provides funds for instrument maintenance and purchase of new instruments that become available. Some instruments have been provided at no or reduced cost by the instrument companies. For more information visit the Instrument Package webpage.

Evaluation of Instruments: A significant effort of the committee has been the evaluation of instruments for environmental measurement. Again the emphasis has been on radiation measurement, initially to accurately measure the photosynthetic photon activity (Tibbitts et al. 1976), and then accurately measure the heat from different types of lamps in different types of chambers. Presently the committee is evaluating sensors for the accurate determination of UV-A and UV-B wavelengths in chambers from different lamps and with different types of barriers that may be utilized.

Quality Assurance Recommendations: These recommendations for environmental measurement were developed to outline types of sensors to use, accuracy in sensors desired, and procedures for calibration of sensors. Sager et al. (2005)


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Last update 29 April 2014