Rhizobox Top Piece For Gas Exchange Measurments & Isotope Labelling
Measuring CO2, O2, N2O or NH4 gas exchange in rhizoboxes is important to determine plant vigor, photosynthetic performance and ecosystem C and GHG fluxes. We thus ofter to build respiration chambers to be tightly placed on top of rhizoboxes, allowing for the convenient measurement of gas fluxes by attaching an instruments of choice, e.g. IR gas analyser or Picarro for CO2 (isotopic) measurements. Isotopes in general are versatile research tools. The VSI top-up chambers for root boxes can thus be used as isotope labelling chambers for plants growing in rhizoboxes to study a range of plant and soil functions such as exudation, water use efficiency, N fixation or transfer of labelled C assimilates to roots and their symbionts.
In the image, the black sleeve attaches tightly to rhizoboxes of the "old" rootbox design style, i.e. without metal spacers. Two connectors at different ends of the chambers can be used to as inlet and outlet for gas fluxes, either for labelling ot to connect a measurement device. Double inlets are available, allowing the positioning of gas in- an outlets inside the chambers according to plant size and architecture. For large top pieces, we recommend ordering an additional fan inside the chamber to ensure complete air mixing.
13C Labelling of Rhizobox-Grown Plants
Global 13C-labelling is used to produce uniformly 13C-labelled plants (here termed as 13C14N plants) and requires either a continuous supply of 13CO2 throughout the whole cultivation or in pulses. The 13CO2 is applied as a substrate which is further converted to all assimilates required to sustain plant metabolism. Therefore, airtight cultivation chambers (labelboxes) with 13CO2 atmosphere become necessary. As the preparation of 13C-enriched plants affords long-term cultivations the technical equipment has to enable the regulation of growth parameters such as temperature, light and the atmospheric humidity as well as the levels of CO2 and O2. The top-up chambers of Vienna Scientific allow to reach this goal cost effectvely and in combination with root and rhizosphere studies, proving a sealed top-up chamber for our "old" rhizobox design - priving an effective solution to label you rhizobox-grown plants over a longer period or in pulses. The closed chambers allow for connecting labeled gas sources and/or to connect isotopic analysers via simple in- and outlets. Advanced chamber mixing (advisable for larger top-up chambers with volumes beyond the mixing capacitiy of connected instruments) can be provided by optional internal ventilators.