Neurobiological View of Plants and Their Body Plan - Communication in Plants: Neuronal Aspects of Plant Life - page 31

2.9
Conclusions and Future Prospects
Our view of plants is changing dramatically, tending away from seeing
them as passive entities subject to environmental forces and organisms
that are designed solely for accumulation of photosynthetic products. The
new view, by contrast, is that plants are dynamic and highly sensitive
organisms, actively and competitively foraging for limited resources both
above and below ground, and that they are also organisms which accurately
compute their circumstances, use sophisticated cost-benefit analysis, and
that take defined actions to mitigate and control diverse environmental in-
sults. Moreover, plants are also capable of a refined recognition of self and
non-self and this leads to territorial behaviour. This new view considers
plants as information-processing organisms with complex communication
throughout the individual plant. Plants are as sophisticated in behaviour
as animals but their potential has been masked because it operates on
time scales many orders of magnitude longer than that operating in ani-
mals.
Plants are sessile organisms. Owing to this lifestyle, the only long-term
response to rapidly changing environments is an equally rapid adaptation;
therefore, plants have developed a very robust signalling and information-
processing apparatus. Signalling in plants encompasses chemical and phys-
ical communication pathways. Chemical communication is based either
on vesicular trafficking pathways, as accomplished also across neuronal
synapses in brains, or through direct cell-cell communication via plas-
modesmata. Moreover, there are numerous signal molecules generated
within cell walls and also as diffusible signals, such as NO, reactive oxygen
species, jasmonates, and ethylene, which penetrate cells from the exocellu-
lar space. On the other hand, physical communication is based on electrical,
hydraulic, and mechanical signals. Besides abundant interactions with the
environment, plants interact with other communicative systems such as
other plants, fungi, nematodes, bacteria, viruses, insects, and predatory
animals. All this great variety of interactions and responses can be em-
braced within the recently introduced field of plant neurobiology.
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