A whole-plant chamber system for parallel gas exchange measurements of Arabidopsis and other herbaceous species

Abstract

BackgroundPhotosynthetic assimilation of carbon is a defining feature of the plant kingdom. The fixation of large amounts of carbon dioxide supports the synthesis of carbohydrates, which make up the bulk of plant biomass. Exact measurements of carbon assimilation rates are therefore crucial due to their impact on the plants metabolism, growth and reproductive success. Commercially available single-leaf cuvettes allow the detailed analysis of many photosynthetic parameters, including gas exchange, of a selected leaf area. However, these cuvettes can be difficult to use with small herbaceous plants such as Arabidopsis thaliana or plants having delicate or textured leaves. Furthermore, data from single leaves can be difficult to scale-up for a plant shoot with a complex architecture and tissues in different physiological states. Therefore, we constructed a versatile system—EGES-1—to simultaneously measure gas exchange in the whole shoots of multiple individual plants. Our system was designed to be able record data continuously over several days.ResultsThe EGES-1 system yielded comparable measurements for eight plants for up to 6 days in stable, physiologically realistic conditions. The chambers seals have negligible permeability to carbon dioxide and the system is designed so as to detect any bulk-flow air leaks. We show that the system can be used to monitor plant responses to changing environmental conditions, such as changes in illumination or stress treatments, and to compare plants with phenotypically severe mutations. By incorporating interchangeable lids, the system could be used to measure photosynthetic gas exchange in several genera such as Arabidopsis, Nicotiana, Pisum, Lotus and Mesembryanthemum.ConclusionEGES-1 can be introduced into a variety of growth facilities and measure gas exchange in the shoots diverse plant species grown in different growth media. It is ideal for comparing photosynthetic carbon assimilation of wild-type and mutant plants and/or plants undergoing selected experimental treatments. The system can deliver valuable data for whole-plant growth studies and help understanding mutant phenotypes. Overall, the EGES-1 is complementary to the readily-available single leaf systems that focus more on the photosynthetic process in within the leaf lamina.Electronic supplementary materialThe online version of this article (doi:10.1186/s13007-015-0089-z) contains supplementary material, which is available to authorized users.

Leaf Starch Turnover Occurs in Long Days and in Falling Light at the End of the Day

“…14 CO 2 labeling was carried out on whole plants using the Plexiglas chamber described by Kölling et al (2015aKölling et al ( , 2015b.Three-week-old plants were placed in the chamber in advance of the experiment, inside a fume cupboard at ;20°C under the lighting conditions described in the text and legends. After sealing the chamber, 75 mCi 14 CO 2 was supplied by injection of lactic acid into NaH 14 CO 3 (specific activity 2.2 TBq mmol 21 ; CO 2 release increased concentration in the chamber by ;8 ppm).…”

“…To establish whether then transferred at dawn to continuous light at 105 (upper data set) or 65 (lower data set) mmol quanta m 22 s 21 . Measurements were made in the growth chamber on individual whole rosettes, using the apparatus described by Kölling et al (2015b). The striped zone marks the subjective night.…”

Modelling nutritional mutualisms: challenges and opportunities for data integration

“…To avoid this scaling discrepancy, nutrient fluxes should be measured at an individual scale whenever possible, such as using photosynthetic chambers to measure whole‐plant carbon uptake (Kölling et al . ). Similarly, predictions concerning carbon‐nutrient exchange rates are best tested at an individual scale with isotopic labelling, as described for cell scale models.…”

Rapid and automated leaf net photosynthetic rate determination for numerous phosphor-converted white-LED lights of different spectral distributions

“…Another limitation of the present LASS system is that it irradiates an area of only 7.1 cm 2 . This limited irradiated area can be su cient for a small leaf chamber such as the LI-6400 or a small whole-plant chamber [25], but it is insu cient for a plant-organ chamber [26] or a whole-plant chamber [27]. This limitation, however, cannot be resolved easily because it requires a scaling up of the LED module by more than several times and a corresponding scaling up of the power supply for the LED module.…”