Life Sciences Commons^™

Emerging Research Techniques & New Instrumentation For Plant Biology, Bruce Bugbee

Techniques and Instruments

We have not achieved an efficient food production system in US Agriculture by manipulating only the environment.

Genetic engineering techniques now allow us to quickly develop new crop cultivars.

Changing The Integration Time Has A Minimal Effect On The Accuracy Of The Apogee / Stellarnet Spectroradiometer, Nick Knighton, Bruce Bugbee

Techniques and Instruments

Changing the integration time has the potential to change the accuracy of the Apogee/StellarNet spectroradiometer. All Apogee/StellarNet spectroradiometers are calibrated to an NIST traceable calibration lamp. This lamp (LI-COR Inc., model 1800-02; Lincoln, NE) has an output of 206.2 µmol m^-2 s^-1, which requires a relatively long integration time (about 500 ms) to obtain a full scale response. Sunlight and high-wattage electric light sources often have a much higher intensity, which require much shorter integration times (10 to100 ms) to prevent light saturation of the detectors. The accuracy might be affected differently by increasing or decreasing integration …

A Mixture Of Barium Sulfate And White Paint Is A Low-Cost Substitute Reflectance Standard For Spectralon®, Nick Knighton, Bruce Bugbee

Techniques and Instruments

Barium sulfate is a white powder that has historically been used as a reference standard (Weidner and Hsia, 1981). It may be a less expensive alternative to higher priced white standards that use sintered PTFE (polytetrafluoroethylene; Spectralon®, Labsphere, Inc., North Sutton, NH). A 500 g bottle of BaSO4 costs $25, whereas reflectance standard made of Spectralon® and with a 99% reflectance factor costs $385. However, pure barium sulfate dries to a powder and easily rubs off surfaces. We sought to increase the durability of barium sulfate by mixing it with untinted white latex paint. Reflectance and durability of different ratios …

Spectrometer Curve Smoothing Using Replicate Scans And Running Averages, Nick Knighton, Bruce Bugbee

Techniques and Instruments

The Boxcar Pixel Smoothing algorithm significantly reduced noise in spectral traces. However, averaging replicate scans did not significantly reduce noise in these studies.

Simulating The Field: How To Grow Plants In Soil Columns In The Greenhouse, Julie K. Chard, Bruce Bugbee

Techniques and Instruments

Why Soil Columns?

In the field of plant research it is often desirable to grow plants under controlled conditions to minimize environmental variability from one treatment to the next. The desired control can be achieved by growing plants in containers in a greenhouse or growth chamber.

Plant growth in soil is straightforward in the field where soils are deep, but soil moisture dynamics are altered significantly in small containers. Drainage in the field results from the depth (thickness) of the soil layer. Gravity alone is not adequate to remove water from agricultural soils in pots.

Soil columns are an improvement …