Although a positive correlation has been observed between leaf temperature and isoprene emission in plants, the physiological role of isoprene emission, which is clearly quite costly to the plant, is still under vigorous debate. One of the most popular hypotheses suggests that isoprene protects the metabolic processes in the leaf, in particular photosynthesis (the process by which plants use light energy to fix CO2 and produce their own “food”), against thermal stress.
To test this hypothesis, scientists Katja Behnke and Jörg-Peter Schnitzler from the Institute for Meteorology and Climate Research of the Research Centre Karlsruhe in Garmisch-Partenkirchen in Germany, together with colleagues from the Universities of Braunschweig and Göttingen, also in Germany, and British Columbia, in Canada, recently applied genetic engineering techniques to obtain transgenic Grey poplar (Populus x canescens) trees with decreased isoprene emission, and examined their tolerance to heat. Their findings have been published in The Plant Journal.
Behnke et al. engineered such poplar trees by suppressing the expression of the gene encoding isoprene synthase (ISPS), the enzyme producing isoprene, by RNA interference (RNAi). They then subjected these trees to transient heat phases of 38-42°C, each followed by phases of recovery at 30°C, and measured the performance of photosynthesis. In these experiments, Behnke et al. observed that photosynthesis in trees that no longer emitted isoprenes was much less efficient under such repeated “heat shocks” (a situation that is similar to what happens in nature, where temperatures around the leaves often oscillate, with short heat spikes). Thus, their results clearly indicate that isoprenes have an important role in protecting the leaves from the harmful effects of high ambient temperature.
How does isoprene confer heat tolerance? Does isoprene act as an antioxidant due to its chemical reactivity? And more generally: Is this effect of significance under natural conditions for poplar and other isoprene-emitting species? The researchers aim to analyse the biophysical and biochemical mechanisms of heat effects on photosynthesis and chloroplasts, and future long-term field trials will test whether the isoprene effect represents a positive adaptive trait for isoprene-producing species.
Davina Quarterman | alfa
How much drought can a forest take?
20.01.2017 | University of California - Davis
Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences