Bring new insights to a variety of studies—from global climate modeling to agricultural efficiency optimization—by tracing the movement of water and carbon through plants.
Rugged and mobile Picarro analyzers enable plant scientists to apply precise stable isotope techniques in the field, gaining unparalleled understanding across a range of spatial and temporal scales. Having immediate results in the field allows researchers to redirect investigations on the fly to get the most interesting data.
Evaporation and transpiration of water from a plant’s leaves transports water from the soil to the atmosphere. In a seminal study, researchers used the oxygen and hydrogen isotope ratios of water vapor collected at different heights above the ground to determine the relative rates of evaporation of water from the ground and transpiration of water from the plants. In addition, the relative transpiration rates of trees were distinguished from those of the underlying grasses. Picarro water isotope analyzers have been used to make measurements such as these.
Critical to plant physiology, leaf waxes are long-lived molecules that can remain in sediments or soils for many years. The hydrogen isotope ratios of these plant-derived waxes are sensitive to climatic conditions, so sediments containing these waxes can reveal information about past climates. However, one must understand the rate of hydrogen incorporation into plant waxes under varying conditions to interpret the sediment results.
Li Gao and coworkers at Brown University used deuterium-enriched water to label plants, and then monitored the rate of deuterium incorporation into the leaf waxes. With the help of a Picarro water isotope analyzer, they demonstrated different rates for different classes of leaf waxes.
One of the most common ways to study nitrogen fixation in plants and bacteria is to expose these organisms to acetylene. The enzyme responsible for nitrogen fixation catalyzes the reaction of acetylene to ethylene. Nicolas Cassar and co-workers have established a technique for monitoring ethylene production using a Picarro analyzer to study the nitrogen fixation rates in bacteria and lichen. Learn more about their study.
13C-labeling of trees
While plants take in CO2 through their leaves, some of that carbon is processed and re-emitted as CO2 at the root. Researchers at Oak Ridge National Lab and the University of Tennessee studied this process by exposing a tree to carbon-13 labeled CO2 and then observing the carbon isotope ratio of various tissues within the tree, as well as the CO2 emitted from the soil using a Picarro carbon isotope analyzer. This allowed them to follow the labeled carbon through a tree, from the leaf, through the trunk and into the roots, where it is processed by soil microbes.
Leaf chambers can be used to study the exchange of CO2 between a leaf and the atmosphere under carefully controlled conditions of temperature, illumination and CO2 levels. Picarro’s carbon isotope analyzer for CO2 can be used to study the different CO2 uptake pathways in the leaf.
Water use efficiency
The carbon isotope ratio in plant materials can be used to calculate the water-use efficiency of a plant, which is a measure of the amount of biomass produced over a growing season, normalized with the amount of water consumed. The quantity is important in agronomy, especially in irrigation systems and in arid regions where a limited amount of rainfall must last for the entire growing season. Research using the carbon isotope ratio with a Picarro analyzer can greatly expanded the understanding of crop water-use efficiency, drought resistance and yield potential.
G2508 – Measure N2O, CH4, CO2, NH3, and H2O simultaneously for soil flux studies.
G2201-i – Continuous, simultaneous measurement of δ13CO2 and δ13CH4 fluxes
G2301 – Continuous measurement of CO2 and CH4 fluxes
G2106 - Measure ethylene at ppb levels