Effect of chronic β-radiation on long-distance electrical signals in wheat and their role in adaptation to heat stress

Electrical Signals, Plant Tolerance to Actions of Stressors, and Programmed Cell Death: Is Interaction Possible?

“…VP is a long-term depolarization signal (minutes, tens of minutes, and even hours) which is considered to be a unique ES in higher plants [ 8 , 31 , 74 ]. A variation potential is induced by local damages (e.g., burning [ 11 , 25 , 96 , 97 , 98 ], gradual heating [ 47 , 99 , 100 ], or wounding [ 11 , 101 ]); it has some specific properties [ 8 , 31 ]. (i) VP has an irregular shape.…”

“…Results have shown that ROS waves can be considered as one of the potential mechanisms of VP. However, VP properties, which are not in accordance with the properties of ROS waves, can also be observed: these are the high velocities of VP propagation (e.g., up to 20 mm s −1 [ 8 ]) and the decrease in the amplitude and/or the VP velocity with the increase in the distance from the damaged zone [ 31 , 47 , 99 ]. Our earlier theoretical analysis [ 99 ] showed that the results can be explained by the complex mechanism of VP propagation (e.g., combination of ROS waves with the turbulent diffusion of H 2 O 2 ).…”

“…Additionally, there are numerous works (e.g., see reviews [ 8 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]) which show the rapid influence of ESs on different physiological processes. It is considered that the result of ES-induced physiological changes is increased plant tolerance to the actions of stressors [ 8 , 34 , 36 , 39 , 40 ] that is supported by the positive influence of electrical signals on the tolerance shown in experimental works [ 41 , 42 , 43 , 44 , 45 , 46 , 47 ]. The relation between ESs and tolerance to stressors can be the basis of the estimation of the action of stressors on plants through measurements of electrical activity [ 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 ].…”

Stochastic Spatial Heterogeneity in Activities of H+-ATP-Ases in Electrically Connected Plant Cells Decreases Threshold for Cooling-Induced Electrical Responses

“…Electrical responses play an important physiological role in plants [ 7 , 8 , 10 , 12 , 13 , 14 ]; they influence the expression of defense genes [ 73 , 74 , 75 ], synthesis of phytohormones [ 37 , 76 , 77 ], photosynthesis [ 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 45 ], phloem mass flow [ 78 , 79 ], respiration [ 32 , 80 , 81 , 82 ], and many other processes. Increasing plant tolerance to the action of stressors is probably the result of the physiological changes [ 13 , 17 , 52 , 83 , 84 , 85 , 86 ]. H + -ATP-ases are key electrogenic transporters for electrical responses in plants because their activities support ion gradients across the plasma membrane at rest [ 4 , 27 , 28 ] and influence thresholds for these responses [ 29 ].…”

“…(ii) There are potential reasons for the heterogeneity in H + -ATP-ase activities including the differences of the activities between different types of plant cells (see e.g., [ 27 ]) and the spatially heterogenous distribution of factors that modify these activities (e.g., light intensity which can activate H + -ATP-ase [ 50 ] and be dependent on the zone of a leaf or depth in the lamina). (iii) Previously, we showed that standard deviations of the magnitudes of the active components of the membrane potentials at rest, which could be used for the estimation of H + -ATP-ase activities, were about 20–30% for pea and wheat [ 32 , 51 , 52 ]. Moreover, our unpublished data shows that standard deviation between the active components of the membrane potentials in mesophyll cells of the same tobacco leaves are 43 ± 11%.…”