- Email: [email protected]
Oscillatory Electrical Response to Osmotic Stress in Soybean Plants
Available online at www.sciencedirect.com
ScienceDirect Procedia Environmental Sciences 29 (2015) 55 – 56
Agriculture and Climate Change - Adapting Crops to Increased Uncertainty (AGRI 2015)
Oscillatory electrical response to osmotic stress in soybean plants Gustavo F.R Saraivaa*, Gustavo M. Souzaa a
Univerisdade do Oeste Paulista, Presidente Priudente-SP, Brazil
Abstract Oscillations in plants can occur at various levels. Their physiological processes evolve during time, presenting a variable dynamics1. Different oscillatory dynamics in different physiological processes in plants have been observed under different environmental conditions. Oscillatory dynamics allow to organisms flexibility in responses to environmental changes2. Recent studies have evidenced the role of electrical signaling in the physiological processes. At the whole-plant level, oscillations of electrical frequency-coded signals are believed to play an important role in communication between the roots and shoots3. The aim of this work was to test the hypothesis that a severe osmotic stress causes changes in the pattern of electrical signaling in soybean plants, allowing discrimination among signs under different water conditions. Two-week-old soybean seedlings were used for the experiments, carried out under constant environmental conditions and inside a Faraday cage. Electrical time series (n=30) were obtained with an electronic acquisition data system. On previous day of experiments, the plants were transferred to hydroponic cultivation and Needle electrodes were inserted into the stem, for acclimatization. Osmotic stress was applied by replacing the nutrient solution by mannitol solution at -2 MPa. Power frequency analysis has confirmed differences in oscillatory characteristic of plant bioelectrical data. Both conditions showed a power spectrum following a power-law distribution, indicating a scale-free pattern of the dynamics. On the other hand, while in the time series scored before osmotic stimuli the range of frequencies from 0.15 to 16 Hz followed the power-law trend, after osmotic stimuli this range was from 0.10 to 5 Hz. Moreover, before stimuli it was observed a second set of frequencies ranging from 11 to 13 Hz, which it was not present in the time series after stimuli. These results have indicates a decrease trend of complexity of the electrical signal to root-shoot communication of soybean seedlings under osmotic stress. © 2015 Published by Elsevier B.V This 2015The TheAuthors. Authors. Published by Elsevier B.V.is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the organizing committee of the Agriculture and Climate Change - Adapting Crops to Peer-review under responsibility the organizing committee of the Agriculture and Climate Change - Adapting Crops to Increased Increased Uncertainty (AGRIof 2015). Uncertainty (AGRI 2015) Keywords: frequency analysis, plant dynamics, root-shot comunnication,
References 1. Luttge U, Hutt M.T. High frequency or ultradian rhythms in plants. Prog Bot 65 (2004) 235-263.
2. Shabala S., Knowles A. Physiological implications of ultradian oscillations by whet roots. Funct Plant Biol 29 (2003) 595-605.
1878-0296 © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the organizing committee of the Agriculture and Climate Change - Adapting Crops to Increased Uncertainty (AGRI 2015) doi:10.1016/j.proenv.2015.07.154
56
Gustavo F.R. Saraiva and Gustavo M. Souza / Procedia Environmental Sciences 29 (2015) 55 – 56
3. Volkov, A. G., Haack, R. A. Insect induces bioelectrochemical signals in potato plants, Bioelectrochem. Bioenerg. 35 (1995) 55–60. * Corresponding author. Tel.: +55 (18) 3229 3255; . E-mail address: [email protected]
ScienceDirect Procedia Environmental Sciences 29 (2015) 55 – 56
Agriculture and Climate Change - Adapting Crops to Increased Uncertainty (AGRI 2015)
Oscillatory electrical response to osmotic stress in soybean plants Gustavo F.R Saraivaa*, Gustavo M. Souzaa a
Univerisdade do Oeste Paulista, Presidente Priudente-SP, Brazil
Abstract Oscillations in plants can occur at various levels. Their physiological processes evolve during time, presenting a variable dynamics1. Different oscillatory dynamics in different physiological processes in plants have been observed under different environmental conditions. Oscillatory dynamics allow to organisms flexibility in responses to environmental changes2. Recent studies have evidenced the role of electrical signaling in the physiological processes. At the whole-plant level, oscillations of electrical frequency-coded signals are believed to play an important role in communication between the roots and shoots3. The aim of this work was to test the hypothesis that a severe osmotic stress causes changes in the pattern of electrical signaling in soybean plants, allowing discrimination among signs under different water conditions. Two-week-old soybean seedlings were used for the experiments, carried out under constant environmental conditions and inside a Faraday cage. Electrical time series (n=30) were obtained with an electronic acquisition data system. On previous day of experiments, the plants were transferred to hydroponic cultivation and Needle electrodes were inserted into the stem, for acclimatization. Osmotic stress was applied by replacing the nutrient solution by mannitol solution at -2 MPa. Power frequency analysis has confirmed differences in oscillatory characteristic of plant bioelectrical data. Both conditions showed a power spectrum following a power-law distribution, indicating a scale-free pattern of the dynamics. On the other hand, while in the time series scored before osmotic stimuli the range of frequencies from 0.15 to 16 Hz followed the power-law trend, after osmotic stimuli this range was from 0.10 to 5 Hz. Moreover, before stimuli it was observed a second set of frequencies ranging from 11 to 13 Hz, which it was not present in the time series after stimuli. These results have indicates a decrease trend of complexity of the electrical signal to root-shoot communication of soybean seedlings under osmotic stress. © 2015 Published by Elsevier B.V This 2015The TheAuthors. Authors. Published by Elsevier B.V.is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the organizing committee of the Agriculture and Climate Change - Adapting Crops to Peer-review under responsibility the organizing committee of the Agriculture and Climate Change - Adapting Crops to Increased Increased Uncertainty (AGRIof 2015). Uncertainty (AGRI 2015) Keywords: frequency analysis, plant dynamics, root-shot comunnication,
References 1. Luttge U, Hutt M.T. High frequency or ultradian rhythms in plants. Prog Bot 65 (2004) 235-263.
2. Shabala S., Knowles A. Physiological implications of ultradian oscillations by whet roots. Funct Plant Biol 29 (2003) 595-605.
1878-0296 © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the organizing committee of the Agriculture and Climate Change - Adapting Crops to Increased Uncertainty (AGRI 2015) doi:10.1016/j.proenv.2015.07.154
56
Gustavo F.R. Saraiva and Gustavo M. Souza / Procedia Environmental Sciences 29 (2015) 55 – 56
3. Volkov, A. G., Haack, R. A. Insect induces bioelectrochemical signals in potato plants, Bioelectrochem. Bioenerg. 35 (1995) 55–60. * Corresponding author. Tel.: +55 (18) 3229 3255; . E-mail address: [email protected]