Research Greenhouses

Space Request

Supplies

Equipment

• Autoclave

• Environmental Chambers

• Light Meter

• Hygrothermograph

• CO2 Analyzer

UCSC Greenhouses
MCDBiology
Sinsheimer Labs
University of California
Santa Cruz, CA 95064
Phone: (831) 459-3485
Fax: (831) 459-3139
Locations & Hours
Maps & Directions

The autoclave available for use in the Sinsheimer greenhouse facility is a small rectangular sterilizer (Consolidated Sterilizer Model SSR-3A-PB), with a chamber size of 20"x20"x38". It is identical to the sterilizers in other parts of Sinsheimer Labs with the exception that it has its own steam generator which must be activated approximately 30-45 minutes before use. Complete instructions for use are available in the greenhouse facility. If you are autoclaving soil make sure that it is spread out on a tray and not more than 1.5" deep so that the heat can penetrate to the center.

A signup sheet is available in the autoclave room (N101A).

Growth chambers and germinators (incubators) are reserved by contacting Jim Velzy, discussing your research experiment, and completing and submitting a greenhouse use form.

GROWTH CHAMBERS
What does a growth chamber do? Plant growth chambers provide precise control of the environmental parameters involved in plant growth: temperature, humidity, photoperiod (daylength) and light intensity. It is important to be able to consistently reproduce these parameters in research. A greenhouse does not provide consistency because of seasonal light and temperature variations. The plant growth chambers used in our facilities (Conviron, Model E-15) are capable of controlling these parameters which, in turn, are programmed into the microprocessor which controls the chamber. As many as 192 different timelines can be programmed into the computer at one time.

FEATURES
Temperature. The temperature sensor continually "reads" the chamber air temperature and "instructs" the heating (or cooling) system to heat (or cool) to maintain the desired temperature to within 0.5C. Light. Light intensity can be varied by either programming differing numbers of light banks to be on and/or by raising or lowering the light banks over the plants. A maximum of ~980 umol can be achieved in this chamber. There are 16-160W Cool White bulbs and 12-60W incandescent bulbs.
Photoperiod. The daylength can be programmed as simply day and night. Or for some experiments, flashes of lights can be programmed into the dark period. Daybreak and sunset can be simulated by "ramping". In this situation, illumination occurs gradually in the "morning" hours and decrease gradually in the "evening" hours. Concomitantly, the temperature increases and then decreases to further simulate natural conditions.
Humidity. The microprocessor regulates the centrifugal atomizing humidifier in coordination with the heating and cooling system to regulate the level of humidity in the growing area.
Other Features. The observation window enables the researcher to see plants inside the chamber without disturbing the internal environmental conditions (except lighting). The chart recorder provides a visual record of the chamber temperature. Alarms notify the researcher that certain parameters (such as temperature and humidity) are deviating past an acceptable point. The growth area is 15 ft2 (1.4 m2). Interior dimensions: 72"W x 30"D x 72"H. The extended height accommodates plants up to 6 ft. tall.

A germinator (incubator) provides a controlled environment for germinating seeds. As with the growth chambers, the germinator provides precise control of the environmental parameters involved in seed germination: temperature, humidity, daylength and light. It is important to be able to provide these parameters consistently in order to maintain optimal germination percentages.

The incubators used in this facility (Percival Model I36LLVL) are capable of controlling these parameters. Light levels are usually lower than that of growth chambers which makes these chambers’ function highly specific for germination and not further stages of plant growth.

The Light Meter available for use is a Licor (LI-189 Quantum/Radiometer/Photometer). The Quantum sensor measures micromoles/m2/sec. The pyranometer measures W/m2; the photometric sensor measures lux, Klux or footcandles. The LI-189 must be re-calibrated with each sensor as units change. Unless specified differently, the quantum sensor is the default sensor attached to the LI-189.

The light meter may be signed out by contacting the greenhouse staff. (x 9-3485).

Hygrothermographs record temperature and humidity simultaneously on a chart which is mounted on a clock driven drum. The instruments available for use are battery operated and can measure one-day or seven-days. It utilizes a bimetallic strip for temperature measurement and a human hair bundle for relative humidity measurements. It is battery operated. The hygrothermograph may be signed out by contacting the greenhouse staff. (x 9-3485).

LI-COR Model LI-6262 CO2/H2O Analyzer

>GENERAL DESCRIPTION
The photosynthetic rate of a leaf, plant, or canopy is calculated from measurements made with a gas exchange system consisting of a chamber to enclose the plant material, a data acquisition system, an infrared CO2 analyzer and sensors to measure several other variables. The LICOR CO2/H2O Analyzer precisely measures CO2 and H2O vapor using infrared gas detection. This combined with a microprocessor based electronic technology provides a unique system of measurement.

OPERATIONAL OVERVIEW
Air (of unknown H2O/CO2 concentration) is continuously circulated through the sample cell of the analyzer while the reference gas, N2, (of zero H2O/CO2 concentration) flows through the reference cell. Infrared radiation is alternately transmitted through each cell path. The signal from the sample cell is compared to the zero gas reference signal to provide an absolute measurement of gas concentration. This concentration is subsequently communicated to us in the digital readout.

READOUT
Digital readout may be in any of the following units: mole fraction (µmole/mole, ppm), partial pressure (pa), mass units (µgram/gram) or dew point (°C) for water. Vapor measurements are automatically corrected for temperature and barometric pressure. The analyzer features digital-to-analog voltage output channels for direct connection to a chart recorder, computer, control device, etc. Each channel has an output range (0-100mV or 0 - 5 volts) which can be proportional to any CO2/H2O output units.

APPLICATIONS
CO2 analyzers are often integrated into control systems for greenhouses and growth chambers to control plant growth and flowering in horticultural crops, to monitor CO2 concentrations for pollution research (involving elevated CO2 concentrations), and to study plant gas exchange.

The analyzer may be signed out by contacting the greenhouse staff at 9-3485.