The induction of localised light stress made possible the finding that will serve to develop more efficient and sustainable crops in the current scenario of climate change.
Researchers from the Universitat Jaume I (UJI), in collaboration with the universities of North Texas and California, have discovered that the leaves of plants have mechanisms to communicate with each other and react in a chain to any change to environmental conditions. The conclusions of this work, in which the professor of Plant Production of the UJI Aurelio Gómez Cadenas has participated, have been published in the journal Science Signaling.
“Our work shows that the leaves of a plant are able to talk to each other, to know how they are in each moment and to perceive how the rest of the leaves are feeling”, says Gómez Cadenas. Adverse situations suffered by a part of the plant, but not by the rest of the plant — such as strong radiation or an attack by a pest or pathogen — are transmitted through the canopy to coordinate the response of the plant. Consequently, “we demonstrated that the exposure of a leaf to strong lighting generates the closing of pores, called stomata, throughout the plant in order to avoid possible dehydration”, says Gómez Cadenas, who points out that this behaviour had not been demonstrated before and “it could be similar to the language of animals or people”, he adds.
The model plant used to do this research was Arabidopsis thaliana. Researchers applied light stress to a single leaf and verified that the rest presented the same behaviour in the face of changing environmental conditions. Aurelio Gómez Cadenas and researcher Sara I. Zandalinas, co-author of this work who defended her doctoral thesis at the UJI a year ago and is currently continuing her research at the University of North Texas, point out that the increase in light located in just one leaf “triggers a wave of chemical signalling in the form of a waterfall to the rest of the leaves of the plant”. Specifically, reactive oxygen species and electrons participate in the propagation of these wave signals of calcium so that the whole plant reacts to the induced light stress as if all of it had received the same amount of light.
The scientific impact of this discovery is very high, in the opinion of Gómez Cadenas, since “it establishes the bases to design new agronomic strategies that increase the tolerance of the crops to the conditions of abiotic stress”. In addition, these results can materialize in genetic improvement programmes and farming operations that “make it possible for species of agronomic interest to produce more efficiently and sustainably in the climate change scenario in which we find ourselves”.
PRESERVATION OF ECOSYSTEMS BEFORE GLOBAL WARMING
The results of this work published in Science Signaling will also serve for future work focused on species whose ecosystems are already severely affected by extreme environmental conditions, often linked to global warming. Ultimately, “our findings will serve to discover the way in which plants coordinate their responses to combined stresses — for example, high temperatures and drought acting simultaneously — and help configure environmental actions to mitigate the effects of climate change on ecosystems with a high ecological value”.
Aurelio Gómez Cadenas is a professor in the Department of Agricultural Sciences and Natural Environment of the Universitat Jaume I, where he heads a multidisciplinary research group that deals with different aspects of biochemistry and molecular biology of plant and animal species subjected to adverse conditions. He also investigates the impact of climate change on agriculture and the evolutionary connection between biological kingdoms.
“Coordinating the overall stomatal response of plants: rapid leaf-to-leaf communication during light stress,” by A.R. Devireddy; R. Mittler at University of North Texas in Denton, TX; S.I. Zandalinas; A. Gómez-Cadenas at Universitat Jaume I in Castello de la Plana, Spain; E. Blumwald at University of California, Davis in Davis, CA. Science Sginaling, 2018 Feb 20;11(518). doi: 10.1126/scisignal.aam9514.