Agriculture Reference
In-Depth Information
each other will give insight into how externally-induced electric fields affect a myriad of
subsystems found within plant life.
Tostartwithanexample:Ifaplantisundersomeformofstress,e.g.,stressfromnothaving
enough water, a number of events are triggered that may cause a plant genetically tuned
to the condition to respond in a protective manner. As will be explained in the sections
that follow, the stimuli of water-stress is sensed by various cells within the plant. This will
subsequently cause the emission of a series of communications signals that are broadcast
to the rest of the plant. Depending upon the type of signal, its strength, and other factors, a
number of physiological responses may be triggered, e.g. the synthesis of ethylene which
bolsters the cell walls against fluid leakage. Plants that are able to survive dry weather
conditionsforextendedperiodsmaydevelopaspecialformoftolerancetotheseconditions
and even pass them on to their offspring. Since the development of genetic adaptations is
linked to how plants are stimulated throughout its life, the plants' electrical environment
(whether natural or artificial) also plays a role.
From an electrical point of view, there are a number of signaling modes that are triggered
by different forms and degrees of stimuli. These broadly include:
• Action potentials
• Variation potentials
• Transient voltages
• Voltage spikes
• Electrochemical voltage gradients
Since most research to date has discovered that the primary response to external electrical
fields is in the generation of signals called action potentials (AP), that will be the topic of
focus in this topic.
What are Action Potentials?
Action potentials can be imagined to be a burst of electrical activity that, once activated,
are capable of traveling throughout the plant. As they work their way through the plant's
biologicalmakeup,theyhavetheabilitytoinitiateawiderangeofphysiologicalresponses,
including those affecting growth, nutrient uptake, reproduction, defense and others. Being
that so many aspects of plant growth are affected by this internal form of electricity, it
makes sense that they form the major basis of the physiological effects realized by plants
when they're subjected to external stimulation.
